The Golden Gate Bridge is a
suspension bridge spanning the
Golden Gate
The Golden Gate is a strait on the west coast of North America that connects San Francisco Bay to the Pacific Ocean. It is defined by the headlands of the San Francisco Peninsula and the Marin Peninsula, and, since 1937, has been spanned by t ...
, the
strait connecting
San Francisco Bay and the
Pacific Ocean
The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the contin ...
. The structure links the U.S. city of
San Francisco
San Francisco (; Spanish for " Saint Francis"), officially the City and County of San Francisco, is the commercial, financial, and cultural center of Northern California. The city proper is the fourth most populous in California and 17th ...
,
California
California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...
—the northern tip of the
San Francisco Peninsula
The San Francisco Peninsula is a peninsula in the San Francisco Bay Area that separates San Francisco Bay from the Pacific Ocean. On its northern tip is the City and County of San Francisco. Its southern base is Mountain View, south of Palo Alt ...
—to
Marin County, carrying both
U.S. Route 101 and
California State Route 1 across the strait. It also carries pedestrian and bicycle traffic, and is designated as part of
U.S. Bicycle Route 95. Being declared one of the
Wonders of the Modern World by the
American Society of Civil Engineers
American(s) may refer to:
* American, something of, from, or related to the United States of America, commonly known as the "United States" or "America"
** Americans, citizens and nationals of the United States of America
** American ancestry, pe ...
, the bridge is one of the most internationally recognized symbols of San Francisco and California. It was initially designed by engineer
Joseph Strauss in 1917. The bridge was named for the
Golden Gate
The Golden Gate is a strait on the west coast of North America that connects San Francisco Bay to the Pacific Ocean. It is defined by the headlands of the San Francisco Peninsula and the Marin Peninsula, and, since 1937, has been spanned by t ...
strait, the channel that it spans.
The
Frommer's
Frommer's is a travel guide book series created by Arthur Frommer in 1957. Frommer's has since expanded to include more than 350 guidebooks in 14 series, as well as other media including an eponymous radio show and a website. In 2017, the compan ...
travel guide describes the Golden Gate Bridge as "possibly the most beautiful, certainly the most photographed, bridge in the world."
At the time of its opening in 1937, it was both the
longest and the
tallest suspension bridge in the world, with a main span of and a total height of .
History
Ferry service
Before the bridge was built, the only practical short route between San Francisco and what is now Marin County was by boat across a section of San Francisco Bay. A ferry service began as early as 1820, with a regularly scheduled service beginning in the 1840s for the purpose of transporting water to San Francisco.
The Sausalito Land and Ferry Company service, launched in 1867, eventually became the Golden Gate Ferry Company, a
Southern Pacific Railroad subsidiary, the largest ferry operation in the world by the late 1920s.
Once for railroad passengers and customers only, Southern Pacific's automobile ferries became very profitable and important to the regional economy. The ferry crossing between the
Hyde Street Pier in San Francisco and
Sausalito Ferry Terminal
Sausalito Ferry Terminal is a ferry terminal in Sausalito, California, connecting Marin County and San Francisco. The station is served by Golden Gate Ferry and Blue & Gold Fleet ferries as well as Golden Gate Transit and Marin Transit bus route ...
in Marin County took approximately 20 minutes and cost $1.00 per vehicle, a price later reduced to compete with the new bridge.
The trip from the
San Francisco Ferry Building
The San Francisco Ferry Building is a terminal for ferries that travel across the San Francisco Bay, a food hall and an office building. It is located on The Embarcadero in San Francisco, California and is served by Golden Gate Ferry and San ...
took 27 minutes.
Many wanted to build a bridge to connect San Francisco to Marin County. San Francisco was the largest American city still served primarily by ferry boats. Because it did not have a permanent link with communities around the bay, the city's growth rate was below the national average.
Many experts said that a bridge could not be built across the strait, which had strong, swirling tides and currents, with water deep at the center of the channel, and frequent strong winds. Experts said that ferocious winds and blinding fogs would prevent construction and operation.
Conception
![Golden gate circa 1891](https://upload.wikimedia.org/wikipedia/commons/5/57/Golden_gate_circa_1891.png)
Although the idea of a bridge spanning the Golden Gate was not new, the proposal that eventually took hold was made in a 1916 ''
San Francisco Bulletin
The ''San Francisco Evening Bulletin'' was a newspaper in San Francisco, founded as the ''Daily Evening Bulletin'' in 1855 by James King of William. King used the newspaper to crusade against political corruption, and built it into having the highe ...
'' article by former engineering student James Wilkins.
San Francisco's City Engineer estimated the cost at $100 million (equivalent to $ billion today), and impractical for the time. He asked bridge engineers whether it could be built for less.
One who responded,
Joseph Strauss, was an ambitious engineer and poet who had, for his
graduate thesis, designed a
railroad bridge across the
Bering Strait.
At the time, Strauss had completed some 400
drawbridges—most of which were inland—and nothing on the scale of the new project.
[Denton, Harry ''et al.'' (2004) "Lonely Planet San Francisco" ''Lonely Planet'', United States, ] Strauss's initial drawings
were for a massive
cantilever
A cantilever is a rigid structural element that extends horizontally and is supported at only one end. Typically it extends from a flat vertical surface such as a wall, to which it must be firmly attached. Like other structural elements, a cant ...
on each side of the strait, connected by a central suspension segment, which Strauss promised could be built for $17 million (equivalent to $ million today).
Local authorities agreed to proceed only on the assurance that Strauss would alter the design and accept input from several consulting project experts. A suspension-bridge design was considered the most practical, because of recent advances in
metallurgy.
Strauss spent more than a decade drumming up support in Northern California. The bridge faced opposition, including litigation, from many sources. The
Department of War was concerned that the bridge would interfere with ship traffic. The
US Navy
The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage ...
feared that a ship collision or sabotage to the bridge could block the entrance to one of its main harbors. Unions demanded guarantees that local workers would be favored for construction jobs.
Southern Pacific Railroad, one of the most powerful business interests in California, opposed the bridge as competition to its ferry fleet and filed a lawsuit against the project, leading to a mass boycott of the ferry service.
In May 1924, Colonel
Herbert Deakyne held the second hearing on the Bridge on behalf of the
Secretary of War
The secretary of war was a member of the U.S. president's Cabinet, beginning with George Washington's administration. A similar position, called either "Secretary at War" or "Secretary of War", had been appointed to serve the Congress of the ...
in a request to use federal land for construction. Deakyne, on behalf of the Secretary of War, approved the transfer of land needed for the bridge structure and leading roads to the "Bridging the Golden Gate Association" and both San Francisco County and Marin County, pending further bridge plans by Strauss. Another ally was the fledgling
automobile industry
The automotive industry comprises a wide range of companies and organizations involved in the design, development, manufacturing, marketing, and selling of motor vehicles. It is one of the world's largest industries by revenue (from 16 % such ...
, which supported the development of roads and bridges to increase demand for automobiles.
The bridge's name was first used when the project was initially discussed in 1917 by
M.M. O'Shaughnessy, city engineer of San Francisco, and Strauss. The name became official with the passage of the
Golden Gate Bridge and Highway District Act by the
state legislature in 1923, creating a
special district to design, build and finance the bridge. San Francisco and most of the counties along the
North Coast of California joined the Golden Gate Bridge District, with the exception being
Humboldt County, whose residents opposed the bridge's construction and the traffic it would generate.
Design
![Golden Gate bridge pillar](https://upload.wikimedia.org/wikipedia/commons/d/d0/Golden_Gate_bridge_pillar.jpg)
Strauss was the chief engineer in charge of the overall design and construction of the bridge project.
However, because he had little understanding or experience with cable-suspension designs,
responsibility for much of the engineering and architecture fell on other experts. Strauss's initial design proposal (two double cantilever spans linked by a central suspension segment) was unacceptable from a visual standpoint. The final graceful suspension design was conceived and championed by
Leon Moisseiff
Leon Solomon Moisseiff (November 10, 1872 – September 3, 1943) was a leading suspension bridge engineer in the United States in the 1920s and 1930s. He was awarded The Franklin Institute's Louis E. Levy Medal in 1933.
His developments of the ...
, the engineer of the
Manhattan Bridge in New York City.
Irving Morrow
Irving Foster Morrow (September 22, 1884 – October 28, 1952) was an American architect best known for designing the Golden Gate Bridge.
Early life
He was born and raised in Oakland, California, the son of Susie (née Kirkman) and James Alexand ...
, a relatively unknown residential architect, designed the overall shape of the bridge towers, the lighting scheme, and
Art Deco
Art Deco, short for the French ''Arts Décoratifs'', and sometimes just called Deco, is a style of visual arts, architecture, and product design, that first appeared in France in the 1910s (just before World War I), and flourished in the Unite ...
elements, such as the tower decorations, streetlights, railing, and walkways. The famous
International Orange
International orange is a color used in the aerospace industry to set objects apart from their surroundings, similar to safety orange, but deeper and with a more reddish tone.
Variations of international orange
Aerospace
The Advanced C ...
color was Morrow's personal selection, winning out over other possibilities, including the US Navy's suggestion that it be painted with black and yellow stripes to ensure visibility by passing ships.
Senior engineer
Charles Alton Ellis
Charles Alton Ellis (18761949) was a professor, structural engineer and mathematician who was chiefly responsible for the structural design of the Golden Gate Bridge. Because of a dispute with Joseph Strauss, he was not recognized for his work w ...
, collaborating remotely with Moisseiff, was the principal engineer of the project.
Moisseiff produced the basic structural design, introducing his "deflection theory" by which a thin, flexible roadway would flex in the wind, greatly reducing stress by transmitting forces via suspension cables to the bridge towers.
Although the Golden Gate Bridge design has proved sound, a later Moisseiff design, the
original Tacoma Narrows Bridge, collapsed in a strong windstorm soon after it was completed, because of an unexpected
aeroelastic flutter
Aeroelasticity is the branch of physics and engineering studying the interactions between the inertial, elastic, and aerodynamic forces occurring while an elastic body is exposed to a fluid flow. The study of aeroelasticity may be broadly classif ...
. Ellis was also tasked with designing a "bridge within a bridge" in the southern abutment, to avoid the need to demolish
Fort Point, a pre–Civil War masonry fortification viewed, even then, as worthy of historic preservation. He penned a graceful steel arch spanning the fort and carrying the roadway to the bridge's southern anchorage.
![Below Golden Gate Bridge](https://upload.wikimedia.org/wikipedia/commons/9/9a/Below_Golden_Gate_Bridge.jpeg)
Ellis was a Greek scholar and mathematician who at one time was a University of Illinois professor of engineering despite having no engineering degree. He eventually earned a degree in civil engineering from the University of Illinois prior to designing the Golden Gate Bridge and spent the last twelve years of his career as a professor at Purdue University. He became an expert in structural design, writing the standard textbook of the time.
Ellis did much of the technical and theoretical work that built the bridge, but he received none of the credit in his lifetime. In November 1931, Strauss fired Ellis and replaced him with a former subordinate, Clifford Paine, ostensibly for wasting too much money sending telegrams back and forth to Moisseiff.
Ellis, obsessed with the project and unable to find work elsewhere during the Depression, continued working 70 hours per week on an unpaid basis, eventually turning in ten volumes of hand calculations.
With an eye toward self-promotion and posterity, Strauss downplayed the contributions of his collaborators who, despite receiving little recognition or compensation,
[ are largely responsible for the final form of the bridge. He succeeded in having himself credited as the person most responsible for the design and vision of the bridge.] Only much later were the contributions of the others on the design team properly appreciated. In May 2007, the Golden Gate Bridge District issued a formal report on 70 years of stewardship of the famous bridge and decided to give Ellis major credit for the design of the bridge.
Finance
The Golden Gate Bridge and Highway District, authorized by an act of the California Legislature
The California State Legislature is a bicameral state legislature consisting of a lower house, the California State Assembly, with 80 members; and an upper house, the California State Senate, with 40 members. Both houses of the Legislatu ...
, was incorporated in 1928 as the official entity to design, construct, and finance the Golden Gate Bridge.[ However, after the ]Wall Street Crash of 1929
The Wall Street Crash of 1929, also known as the Great Crash, was a major American stock market crash that occurred in the autumn of 1929. It started in September and ended late in October, when share prices on the New York Stock Exchange coll ...
, the District was unable to raise the construction funds, so it lobbied for a $30 million bond measure
A municipal bond, commonly known as a muni, is a bond issued by state or local governments, or entities they create such as authorities and special districts. In the United States, interest income received by holders of municipal bonds is often, ...
(equivalent to $ million today). The bonds were approved in November 1930, by votes in the counties affected by the bridge. The construction budget at the time of approval was $27 million ($ million today). However, the District was unable to sell the bonds until 1932, when Amadeo Giannini
Amadeo Pietro Giannini (), also known as Amadeo Peter Giannini or A. P. Giannini (May 6, 1870 – June 3, 1949) was an American banker who founded the Bank of Italy, which became Bank of America. Giannini is credited as the inventor of many modern ...
, the founder of San Francisco–based Bank of America
The Bank of America Corporation (often abbreviated BofA or BoA) is an American multinational investment bank and financial services holding company headquartered at the Bank of America Corporate Center in Charlotte, North Carolina. The bank ...
, agreed on behalf of his bank to buy the entire issue in order to help the local economy.
Construction
Construction began on January 5, 1933. The project cost more than $35 million ($ in dollars), and was completed ahead of schedule and $1.3 million under budget (equivalent to $ million today).
The Golden Gate Bridge construction project was carried out by the McClintic-Marshall Construction Co., a subsidiary of Bethlehem Steel Corporation
The Bethlehem Steel Corporation was an American steelmaking company headquartered in Bethlehem, Pennsylvania. For most of the 20th century, it was one of the world's largest steel producing and shipbuilding companies. At the height of its succ ...
founded by Howard H. McClintic and Charles D. Marshall, both of Lehigh University
Lehigh University (LU) is a private research university in Bethlehem, Pennsylvania in the Lehigh Valley region of eastern Pennsylvania. The university was established in 1865 by businessman Asa Packer and was originally affiliated with the Epi ...
.
Strauss remained head of the project, overseeing day-to-day construction and making some groundbreaking contributions. A graduate of the University of Cincinnati
The University of Cincinnati (UC or Cincinnati) is a public research university in Cincinnati, Ohio. Founded in 1819 as Cincinnati College, it is the oldest institution of higher education in Cincinnati and has an annual enrollment of over 44,0 ...
, he placed a brick from his alma mater's demolished McMicken Hall in the south anchorage before the concrete was poured.
Strauss also innovated the use of movable safety netting beneath the men working, which saved many lives. Nineteen men saved by the nets over the course of the project formed the Half Way to Hell Club. Nonetheless eleven men were killed in falls, ten on February 17, 1937, when a scaffold with twelve men on it, and secured by undersized bolts, fell into and broke through the safety net; two of the twelve survived the fall into the water.
The bridge opened May 27, 1937.
The Bridge Round House
A bridge is a structure built to span a physical obstacle (such as a body of water, valley, road, or rail) without blocking the way underneath. It is constructed for the purpose of providing passage over the obstacle, which is usually somethi ...
diner was then included in the southeastern end of the Golden Gate Bridge, adjacent to the tourist plaza which was renovated in 2012.[
] The Bridge Round House, an Art Deco
Art Deco, short for the French ''Arts Décoratifs'', and sometimes just called Deco, is a style of visual arts, architecture, and product design, that first appeared in France in the 1910s (just before World War I), and flourished in the Unite ...
design by Alfred Finnila Finnila's Finnish Baths—a.k.a. ''Finnila's''—was a Finnish bathhouse and a health club in San Francisco, California. It served the general public from circa 1910 to September, 2000. ''Finnila's'' was located in the Castro District of San Francis ...
completed in 1938, has been popular throughout the years as a starting point for various commercial tours of the bridge and an unofficial gift shop. The diner was renovated in 2012[ and the gift shop was then removed as a new, official gift shop has been included in the adjacent plaza.][
During the bridge work, the Assistant Civil Engineer of California ]Alfred Finnila Finnila's Finnish Baths—a.k.a. ''Finnila's''—was a Finnish bathhouse and a health club in San Francisco, California. It served the general public from circa 1910 to September, 2000. ''Finnila's'' was located in the Castro District of San Francis ...
had overseen the entire iron work of the bridge as well as half of the bridge's road work.
Contributors
Plaque of the major contributors to the Golden Gate Bridge lists contractors, engineering-staff, directors and officers:
Contractors
* Foundations - Pacific Bridge Company
Pacific Bridge Company was a large engineering and construction company. During World War II, Pacific Bridge Company of Alameda, California was selected to build US Navy Auxiliary Repair Docks (ARD) a type of Auxiliary floating drydock and Ty ...
* Anchorages - Barrett & Hilp
* Structural steel - Main span - Bethlehem Steel Company Incorporated
* Approach steel - J.H. Pomeroy & Company Incorporated - Raymond Concrete Pile Company
* Cables - John A. Roebling's Sons Company
* Electrical work - Alta Electric and Mechanical Company Incorporated
* Bridge deck - Pacific Bridge Company
* Presidio Approach Roads and Viaducts - Easton & Smith
* Toll Plaza - Barrett & Hilp
Engineering staff
* Chief engineer - Joseph B. Strauss
* Principal assistant engineer - Clifford E. Paine
* Resident engineer - Russell Cone
* Assistant engineer - Charles Clarahan Jr., Dwight N. Wetherell
* Consulting engineer - O.H. Ammann, Charles Derleth Jr., Leon S. Moisseiff
* Consulting traffic engineer - Sydney W. Taylor, Jr.
* Consulting architect - Irving F. Morrow
* Consulting geologist - Andrew C. Lawson, Allan E. Sedgwick
Directors
* San Francisco - William P. Filmer, Richard J. Welch, Warren Shannon, Hugo D. Newhouse, Arthur M. Brown, Jr., John P. McLaughlin, William D. Hadeler, C.A. Henry, Francis V. Keesling, William P. Stanton, George T. Cameron
* Marin County - Robert H. Trumbull, Harry Lutgens
* Napa County - Thomas Maxwell
* Sonoma County - Frank P. Doyle, Joseph A. McMinn
* Mendocino County - A. R. O'Brien
* Del Norte County - Henry Westbrook, Jr., Milton M. McVay
Officers
* President - William P. Filmer
* Vice President - Robert H. Trumbull
* General manager - James Reed, Alan McDonald
* Chief engineer - Joseph B. Strauss
* Secretary - W. W. Felt, Jr.
* Auditor - Roy S. West, John R. Ruckstell
* Attorney - George H. Harlan
Torsional bracing retrofit
On December 1, 1951, a windstorm revealed swaying and rolling instabilities of the bridge, resulting in its closure. In 1953 and 1954, the bridge was retrofitted with lateral and diagonal bracing that connected the lower chords of the two side trusses. This bracing stiffened the bridge deck in torsion so that it would better resist the types of twisting that had destroyed the Tacoma Narrows Bridge
The Tacoma Narrows Bridge is a pair of twin suspension bridges that span the Tacoma Narrows strait of Puget Sound in Pierce County, Washington. The bridges connect the city of Tacoma with the Kitsap Peninsula and carry State Route 16 (know ...
in 1940.
Bridge deck replacement (1982–1986)
The original bridge used a concrete
Concrete is a composite material composed of fine and coarse aggregate bonded together with a fluid cement (cement paste) that hardens (cures) over time. Concrete is the second-most-used substance in the world after water, and is the most wid ...
deck. Salt
Salt is a mineral composed primarily of sodium chloride (NaCl), a chemical compound belonging to the larger class of salts; salt in the form of a natural crystalline mineral is known as rock salt or halite. Salt is present in vast quant ...
carried by fog or mist reached the rebar, causing corrosion
Corrosion is a natural process that converts a refined metal into a more chemically stable oxide. It is the gradual deterioration of materials (usually a metal) by chemical or electrochemical reaction with their environment. Corrosion engi ...
and concrete spall
Spall are fragments of a material that are broken off a larger solid body. It can be produced by a variety of mechanisms, including as a result of projectile impact, corrosion, weathering, cavitation, or excessive rolling pressure (as in a ba ...
ing. From 1982 to 1986, the original bridge deck, in 747 sections, was systematically replaced with a 40% lighter, and stronger, steel orthotropic deck
An orthotropic bridge or orthotropic deck is typically one whose fabricated deck consists of a structural steel deck plate stiffened either longitudinally with ribs or transversely, or in both directions. This allows the fabricated deck both t ...
panels, over 401 nights without closing the roadway completely to traffic. The roadway was also widened by two feet, resulting in outside curb lane width of 11 feet, instead of 10 feet for the inside lanes. This deck replacement was the bridge's greatest engineering project since it was built and cost over $68 million.
Opening festivities, and 50th and 75th anniversaries
The bridge-opening celebration in 1937 began on May 27 and lasted for one week. The day before vehicle traffic was allowed, 200,000 people crossed either on foot or on roller skates. On opening day, Mayor Angelo Rossi and other officials rode the ferry to Marin, then crossed the bridge in a motorcade past three ceremonial "barriers," the last a blockade of beauty queens who required Joseph Strauss to present the bridge to the Highway District before allowing him to pass. An official song, "There's a Silver Moon on the Golden Gate "There's a Silver Moon on the Golden Gate" is the official song commemorating the opening the Golden Gate Bridge in May 1937. It was written by Charles Tobias, Bob Rothberg and Joseph Meyer. Music publishers, Irving Berlin Inc.
The song was fir ...
," was chosen to commemorate the event. Strauss wrote a poem that is now on the Golden Gate Bridge entitled "The Mighty Task is Done." The next day, President Franklin D. Roosevelt
Franklin Delano Roosevelt (; ; January 30, 1882April 12, 1945), often referred to by his initials FDR, was an American politician and attorney who served as the 32nd president of the United States from 1933 until his death in 1945. As the ...
pushed a button in Washington, D.C. signaling the official start of vehicle traffic over the Bridge at noon. Weeks of civil and cultural activities called "the Fiesta" followed. A statue of Strauss was moved in 1955 to a site near the bridge.
As part of the fiftieth anniversary celebration in 1987, the Golden Gate Bridge district again closed the bridge to automobile traffic and allowed pedestrians to cross it on May 24. This Sunday morning celebration attracted 750,000 to 1,000,000 people, and ineffective crowd control meant the bridge became congested with roughly 300,000 people, causing the center span of the bridge to flatten out under the weight. Although the bridge is designed to flex in that way under heavy loads, and was estimated not to have exceeded 40% of the yielding stress of the suspension cables, bridge officials stated that uncontrolled pedestrian access was not being considered as part of the 75th anniversary on Sunday, May 27, 2012, because of the additional law enforcement costs required "since 9/11."
File:GoldenGateBridge openingday.jpg, A pedestrian poses at the old railing on opening day, 1937.
File:Golden Gate Bridge Opening - (1936).ogg, Opening of the Golden Gate Bridge
File:Invitation to Golden Gate Bridge opening, 1937.jpg, Official invitation to the opening of the bridge. This copy was sent to the City of Seattle
Seattle ( ) is a seaport city on the West Coast of the United States. It is the seat of King County, Washington. With a 2020 population of 737,015, it is the largest city in both the state of Washington and the Pacific Northwest regio ...
.
''Commemorative Bricks''
On the 50th anniversary of the Golden Gate Bridge in 1987, individuals and organizations were invited to buy a commemorative brick to fund the 50th anniversary celebration. Those bricks were installed on the ground creating a brick promenade. Its location is shown on the map.
More than 7,500 donors responded, personalizing their brick with inscriptions and tributes.
Unfortunately, 25 years later, for the upcoming 75th of the Golden Gate Bridge, the need for a DDA compliant area, as the slope was too steep, implied remodeling the whole promenade. Doing so, and contractors being unable to properly take bricks out one by one, the brick promenade was demolished and the contributors were unable to get their bricks back.
However, to honor and respect their contributions, all the donors' names and the inscriptions they had chosen for their bricks have been preserved and written on panels.
The panels are located inside the "Equator Coffees", on its rounded walls. The names and inscriptions are listed in the alphabetical order, to make them easier to read and find.
Thi
website
has been keeping a maps view of the original brick promenade and the database of all donors' names and inscriptions, to help find and locate them on the original layout. As of October 2022, the website is unfortunately down.
Structural specifications
Until 1964, the Golden Gate Bridge had the longest suspension bridge main span in the world, at . Since 1964 its main span length has been surpassed by seventeen bridges; it now has the second-longest main span in the Americas
The Americas, which are sometimes collectively called America, are a landmass comprising the totality of North and South America. The Americas make up most of the land in Earth's Western Hemisphere and comprise the New World.
Along with th ...
, after the Verrazzano-Narrows Bridge
The Verrazzano-Narrows Bridge ( ) is a suspension bridge connecting the New York City boroughs of Staten Island and Brooklyn. It spans the Narrows, a body of water linking the relatively enclosed New York Harbor with Lower New York Bay and t ...
in New York City. The total length of the Golden Gate Bridge from abutment
An abutment is the substructure at the ends of a bridge span or dam supporting its superstructure. Single-span bridges have abutments at each end which provide vertical and lateral support for the span, as well as acting as retaining walls ...
to abutment is .
The Golden Gate Bridge's clearance above high water averages while its towers, at above the water, were the world's tallest on a suspension bridge until 1993 when it was surpassed by the Mezcala Bridge
The Mezcala Bridge (also known as the Mezcala-Solidaridad Bridge), is a cable-stayed bridge located in the state of Guerrero on Highway 95D in Mexico. It spans the Balsas River (known locally as the Mezcala River) close to the western Pacific coa ...
, in Mexico.
The weight of the roadway is hung from 250 pairs of vertical suspender ropes, which are attached to two main cables. The main cables pass over the two main towers and are fixed in concrete at each end. Each cable is made of 27,572 strands of wire. The total length of galvanized steel wire
Overhead power cabling. The conductor consists of seven strands of steel (centre, high tensile strength), surrounded by four outer layers of aluminium (high conductivity). Sample diameter 40 mm
A wire is a flexible strand of metal.
Wire is c ...
used to fabricate both main cables is estimated to be . Each of the bridge's two towers has approximately 600,000 rivet
A rivet is a permanent mechanical fastener. Before being installed, a rivet consists of a smooth cylindrical shaft with a head on one end. The end opposite to the head is called the ''tail''. On installation, the rivet is placed in a punched ...
s.
In the 1960s, when the Bay Area Rapid Transit system (BART) was being planned, the engineering community had conflicting opinions about the feasibility of running train tracks north to Marin County over the bridge. In June 1961, consultants hired by BART completed a study that determined the bridge's suspension section was capable of supporting service on a new lower deck. In July 1961, one of the bridge's consulting engineers, Clifford Paine, disagreed with their conclusion. In January 1962, due to more conflicting reports on feasibility, the bridge's board of directors appointed an engineering review board to analyze all the reports. The review board's report, released in April 1962, concluded that running BART on the bridge was not advisable.
Aesthetics
Aesthetics was the foremost reason why the first design of Joseph Strauss was rejected. Upon re-submission of his bridge construction plan, he added details, such as lighting, to outline the bridge's cables and towers. In 1999, it was ranked fifth on the '' List of America's Favorite Architecture'' by the American Institute of Architects
The American Institute of Architects (AIA) is a professional organization for architects in the United States. Headquartered in Washington, D.C., the AIA offers education, government advocacy, community redevelopment, and public outreach to su ...
.
The color of the bridge is officially an orange vermilion
Vermilion (sometimes vermillion) is a color, color family, and pigment most often made, since antiquity until the 19th century, from the powdered mineral cinnabar (a form of mercury sulfide, which is toxic) and its corresponding color. It i ...
called ''international orange
International orange is a color used in the aerospace industry to set objects apart from their surroundings, similar to safety orange, but deeper and with a more reddish tone.
Variations of international orange
Aerospace
The Advanced C ...
''. The color was selected by consulting architect Irving Morrow because it complements the natural surroundings and enhances the bridge's visibility in fog.
The bridge was originally painted with red lead
Red is the color at the long wavelength end of the visible spectrum of light, next to orange and opposite violet. It has a dominant wavelength of approximately 625–740 nanometres. It is a primary color in the RGB color model and a secondar ...
primer and a lead-based topcoat, which was touched up as required. In the mid-1960s, a program was started to improve corrosion protection by stripping the original paint and repainting the bridge with zinc silicate primer and vinyl
Vinyl may refer to:
Chemistry
* Polyvinyl chloride (PVC), a particular vinyl polymer
* Vinyl cation, a type of carbocation
* Vinyl group, a broad class of organic molecules in chemistry
* Vinyl polymer, a group of polymers derived from vinyl ...
topcoats. Since 1990, acrylic
Acrylic may refer to:
Chemicals and materials
* Acrylic acid, the simplest acrylic compound
* Acrylate polymer, a group of polymers (plastics) noted for transparency and elasticity
* Acrylic resin, a group of related thermoplastic or thermosett ...
topcoats have been used instead for air-quality reasons. The program was completed in 1995 and it is now maintained by 38 painters who touch up the paintwork where it becomes seriously corroded.
The ongoing maintenance task of painting the bridge is continuous.
File:The Bridge (August 2013).jpg, A view of the Golden Gate Bridge from the Marin Headlands on a foggy morning at sunrise
File:Golden Gate Bridge tower views 01.jpg, View of Marin from the south tower
File:Golden Gate Bridge tower views 18.jpg, Top of the south tower
Traffic
Most maps and signage mark the bridge as part of the concurrency between U.S. Route 101 and California State Route 1. Although part of the National Highway System, the bridge is not officially part of California's Highway System. For example, under the California Streets and Highways Code § 401, Route 101 ends at "the approach to the Golden Gate Bridge" and then resumes at "a point in Marin County opposite San Francisco". The Golden Gate Bridge, Highway and Transportation District
The Golden Gate Bridge, Highway and Transportation District is a special-purpose district that owns and operates three regional transportation assets in the San Francisco Bay Area: the iconic Golden Gate Bridge, the Golden Gate Ferry system and ...
has jurisdiction over the segment of highway that crosses the bridge instead of the California Department of Transportation
The California Department of Transportation (Caltrans) is an executive department of the U.S. state of California. The department is part of the cabinet-level California State Transportation Agency (CalSTA). Caltrans is headquartered in Sacr ...
(Caltrans).
The movable median barrier between the lanes is moved several times daily to conform to traffic patterns. On weekday mornings, traffic flows mostly southbound into the city, so four of the six lanes run southbound. Conversely, on weekday afternoons, four lanes run northbound. During off-peak periods and weekends, traffic is split with three lanes in each direction.
From 1968 to 2015, opposing traffic was separated by small, plastic pylons; during that time, there were 16 fatalities resulting from 128 head-on collisions. To improve safety, the speed limit
Speed limits on road traffic, as used in most countries, set the legal maximum speed at which vehicles may travel on a given stretch of road. Speed limits are generally indicated on a traffic sign reflecting the maximum permitted speed - expre ...
on the Golden Gate Bridge was reduced from on October 1, 1983.[ Although there had been discussion concerning the installation of a movable barrier since the 1980s, only in March 2005 did the Bridge Board of Directors commit to finding funding to complete the $2 million study required prior to the installation of a movable median barrier.] Installation of the resulting barrier was completed on January 11, 2015, following a closure of 45.5 hours to private vehicle traffic, the longest in the bridge's history. The new barrier system, including the zipper trucks, cost approximately $30.3 million to purchase and install.
The bridge carries about 112,000 vehicles per day according to the Golden Gate Bridge Highway and Transportation District.
Usage and tourism
The bridge is popular with pedestrians and bicyclists, and was built with walkways on either side of the six vehicle traffic lanes. Initially, they were separated from the traffic lanes by only a metal curb, but railings between the walkways and the traffic lanes were added in 2003, primarily as a measure to prevent bicyclists from falling into the roadway. The bridge was designated as part of U.S. Bicycle Route 95 in 2021.
The main walkway is on the eastern side, and is open for use by both pedestrians and bicycles in the morning to mid-afternoon during weekdays (5:00 a.m. to 3:30 p.m.), and to pedestrians only for the remaining daylight hours (until 6:00 p.m., or 9:00 p.m. during DST
Daylight saving time (DST), also referred to as daylight savings time or simply daylight time (United States, Canada, and Australia), and summer time (United Kingdom, European Union, and others), is the practice of advancing clocks (typicall ...
). The eastern walkway is reserved for pedestrians on weekends (5:00 a.m. to 6:00 p.m., or 9:00 p.m. during DST), and is open exclusively to bicyclists in the evening and overnight, when it is closed to pedestrians. The western walkway is open only for bicyclists and only during the hours when they are not allowed on the eastern walkway.
Bus service across the bridge is provided by two public transportation agencies: San Francisco Muni
The San Francisco Municipal Railway (SF Muni or Muni), is the public transit system for the City and County of San Francisco. It operates a system of bus routes (including trolleybuses), the Muni Metro light rail system, three historic cable ...
and Golden Gate Transit
Golden Gate Transit (GGT) is a public transportation system serving the North Bay region of the San Francisco Bay Area in California, United States. It primarily serves Marin County, Sonoma County, and San Francisco, and also provides limited s ...
. Muni offers Saturday and Sunday service on the Marin Headlands Express bus line, and Golden Gate Transit runs numerous bus lines throughout the week. The southern end of the bridge, near the toll plaza and parking lot, is also accessible daily from 5:30 a.m. to midnight by Muni line 28. The Marin Airporter, a private company, also offers service across the bridge between Marin County and San Francisco International Airport.
A visitor center
A visitor center or centre (see American and British English spelling differences), visitor information center, tourist information center, is a physical location that provides tourist information to visitors.
Types of visitor center
A visi ...
and gift shop, originally called the "Bridge Pavilion" (since renamed the “Golden Gate Bridge Welcome Center”), is located on the San Francisco side of the bridge, adjacent to the southeast parking lot. It opened in 2012, in time for the bridge's 75th-anniversary celebration. A cafe, outdoor exhibits, and restroom facilities are located nearby. On the Marin side of the bridge, only accessible from the northbound lanes, is the H. Dana Bower Rest Area and Vista Point, named after the first landscape architect for the California Division of Highways.
Lands and waters under and around the bridge are homes to varieties of wildlife such as bobcats, harbor seals, and sea lions. Three species of cetaceans (whales) that had been absent in the area for many years have shown recent recoveries/(re)colonizations in the vicinity of the bridge; researchers studying them have encouraged stronger protections and recommended that the public watch them from the bridge or from land, or use a local whale watching
Whale watching is the practice of observing whales and dolphins (cetaceans) in their natural habitat. Whale watching is mostly a recreational activity (cf. birdwatching), but it can also serve scientific and/or educational purposes.Hoyt, E. 2 ...
operator.
Tolls
Current toll rates
Tolls are only collected from southbound traffic at the toll plaza on the San Francisco side of the bridge. All-electronic tolling
Open road tolling (ORT), also called all-electronic tolling, cashless tolling, or free-flow tolling, is the collection of tolls on toll roads without the use of toll booths. An electronic toll collection system is usually used instead. The ma ...
has been in effect since 2013, and drivers may either pay using the FasTrak
FasTrak is the electronic toll collection (ETC) system used in the state of California in the United States. The system is used statewide on all of the toll roads, toll bridges, and high-occupancy toll lanes along the California Freeway an ...
electronic toll collection device, using the license plate tolling program, or via a one time payment online. Effective , the regular toll rate for passenger cars is $8.80, with FasTrak users paying a discounted toll of $8.40. During peak traffic hours, carpool
Carpooling (also car-sharing, ride-sharing and lift-sharing) is the sharing of Automobile, car journeys so that more than one person travels in a car, and prevents the need for others to have to drive to a location themselves.
By having more ...
vehicles carrying three or more people, or motorcycles may pay a discounted toll of $6.40 if they have FasTrak and use the designated carpool lane. Drivers must pay within 48 hours after crossing the bridge or they will be sent a toll violation invoice. The toll violation penalty is $9.40, and additional fees will be added if it is not paid within 21 days.
Historical toll rates
When the Golden Gate Bridge opened in 1937, the toll was 50cents per car (equivalent to $ in ), collected in each direction. In 1950 it was reduced to 40cents each way ($ in ), then lowered to 25cents in 1955 ($ in ). In 1968, the bridge was converted to only collect tolls from southbound traffic, with the toll amount reset back to 50cents ($ in ).
The last of the construction bonds were retired in 1971, with $35 million (equivalent to $M in ) in principal and nearly $39 million ($M in ) in interest raised entirely from bridge tolls. Tolls continued to be collected and subsequently incrementally raised; in 1991, the toll was raised a dollar to $3.00 (equivalent to $ in ).
The bridge began accepting tolls via the FasTrak
FasTrak is the electronic toll collection (ETC) system used in the state of California in the United States. The system is used statewide on all of the toll roads, toll bridges, and high-occupancy toll lanes along the California Freeway an ...
electronic toll collection system in 2002, with $4 tolls for FasTrak users and $5 for those paying cash (equivalent to $ and $ respectively in ).[ In November 2006, the Golden Gate Bridge, Highway and Transportation District recommended a ]corporate sponsorship
Sponsoring something (or someone) is the act of supporting an event, activity, person, or organization financially or through the provision of products or services. The individual or group that provides the support, similar to a benefactor, is k ...
program for the bridge to address its operating deficit, projected at $80 million over five years. The District promised that the proposal, which it called a "partnership program", would not include changing the name of the bridge or placing advertising on the bridge itself. In October 2007, the Board unanimously voted to discontinue the proposal and seek additional revenue through other means, most likely a toll increase. The District later increased the toll amounts in 2008 to $5 for FasTrak users and $6 to those paying cash (equivalent to $ and $ respectively in ).[
In an effort to save $19.2 million over the following 10 years, the Golden Gate District voted in January 2011 to eliminate all toll takers by 2012 and use only ]open road tolling
Open road tolling (ORT), also called all-electronic tolling, cashless tolling, or free-flow tolling, is the collection of tolls on toll roads without the use of toll booths. An electronic toll collection system is usually used instead. The ma ...
. Subsequently, this was delayed and toll taker elimination occurred in March 2013. The cost savings have been revised to $19 million over an eight-year period. In addition to FasTrak, the Golden Gate Transportation District implemented the use of license plate tolling (branded as "Pay-by-Plate"), and also a one-time payment system for drivers to pay before or after their trip on the bridge. Twenty-eight positions were eliminated as part of this plan.
On April 7, 2014, the toll for users of FasTrak was increased from $5 to $6 (equivalent to $ in ), while the toll for drivers using either the license plate tolling or the one time payment system was raised from $6 to $7 (equivalent to $ in ). Bicycle, pedestrian, and northbound motor vehicle traffic remain toll free. For vehicles with more than two axles, the toll rate was $7 per axle for those using license plate tolling or the one time payment system, and $6 per axle for FasTrak users. During peak traffic hours, carpool vehicles carrying two or more people and motorcycles paid a discounted toll of $4 (equivalent to $ in ); drivers must have had Fastrak to take advantage of this carpool rate. The Golden Gate Transportation District then increased the tolls by 25cents in July 2015, and then by another 25cents each of the next three years.
In March 2019, the Golden Gate Transportation District approved a plan to implement 35-cent annual toll increases through 2023, except for the toll-by-plate program which will increase by 20cents per year.
Congestion pricing
In March 2008, the Golden Gate Bridge District board approved a resolution to start congestion pricing
Congestion pricing or congestion charges is a system of surcharging users of public goods that are subject to congestion through excess demand, such as through higher peak charges for use of bus services, electricity, metros, railways, tele ...
at the Golden Gate Bridge, charging higher tolls during the peak hours, but rising and falling depending on traffic levels. This decision allowed the Bay Area to meet the federal requirement to receive $158 million in federal transportation funds from USDOT
The United States Department of Transportation (USDOT or DOT) is one of the executive departments of the U.S. federal government. It is headed by the secretary of transportation, who reports directly to the President of the United States and ...
Urban Partnership grant. As a condition of the grant, the congestion toll was to be in place by September 2009.
In August 2008, transportation officials ended the congestion pricing program in favor of varying rates for metered parking along the route to the bridge including on Lombard Street and Van Ness Avenue
Van Ness Avenue is a north–south thoroughfare in San Francisco, California. Originally named Marlette Street, the street was renamed Van Ness Avenue in honor of the city's sixth mayor, James Van Ness.
The main part of Van Ness Avenue runs fro ...
.
Issues
Suicides
The Golden Gate Bridge is the most used suicide site in the world. The deck is about above the water. After a fall of four seconds, jumpers
Jumper or Jumpers may refer to:
Clothing
* Jumper (sweater), a long-sleeve article of clothing; also called a top, pullover, or sweater
**A waist-length top garment of dense wool, part of the Royal Navy uniform and the uniform of the United Stat ...
hit the water at around . Most die from impact trauma
Trauma most often refers to:
* Major trauma, in physical medicine, severe physical injury caused by an external source
* Psychological trauma, a type of damage to the psyche that occurs as a result of a severely distressing event
*Traumatic i ...
. About 5% survive the initial impact but generally drown
Drowning is a type of suffocation induced by the submersion of the mouth and nose in a liquid. Most instances of fatal drowning occur alone or in situations where others present are either unaware of the victim's situation or unable to offer as ...
or die of hypothermia
Hypothermia is defined as a body core temperature below in humans. Symptoms depend on the temperature. In mild hypothermia, there is shivering and mental confusion. In moderate hypothermia, shivering stops and confusion increases. In severe ...
in the cold water.
After years of debate and an estimated more than 1,500 deaths, suicide barriers, consisting of a stainless steel net extending 20 feet from the bridge and supported by structural steel 20 feet under the walkway, began to be installed in April 2017. Construction was first estimated to take approximately four years at a cost of over $200 million. In December 2019, it was reported that construction of the suicide prevention net had fallen two years behind schedule because the lead contractor, Shimmick Construction Co., had been sold in 2017, leading to the slowdown of several existing projects. As of December 2019, the completion date for the Golden Gate Bridge net was set for 2023.
Wind
The Golden Gate Bridge was designed to safely withstand winds of up to . Until 2008, the bridge was closed because of weather conditions only three times: on December 1, 1951, because of gusts of ; on December 23, 1982, because of winds of ; and on December 3, 1983, because of wind gusts of . An anemometer
In meteorology, an anemometer () is a device that measures wind speed and direction. It is a common instrument used in weather stations. The earliest known description of an anemometer was by Italian architect and author Leon Battista Alberti ...
placed midway between the two towers on the west side of the bridge has been used to measure wind speeds. Another anemometer was placed on one of the towers.
As part of the retrofitting of the bridge and installation of the suicide barrier, starting in 2019 the railings on the west side of the pedestrian walkway were replaced with thinner, more flexible slats in order to improve the bridge's aerodynamic tolerance of high wind to . Starting in June 2020, reports were received of a loud hum, heard across San Francisco and Marin County, produced by the new railing slats when a strong west wind was blowing. The sound had been predicted from wind tunnel
Wind tunnels are large tubes with air blowing through them which are used to replicate the interaction between air and an object flying through the air or moving along the ground. Researchers use wind tunnels to learn more about how an aircraft ...
tests,[ but not included in the environmental impact report; ways of ameliorating it are being considered. An independent engineering analysis of a 2020 sound recording of the tones concludes that the singing noise comprises a variety of Aeolian tones (the sound produced by air flowing past a sharp edge), arising in this case from the ambient wind blowing across metal slats of the newly installed sidewalk railings. The tones observed were frequencies of 354, 398, 439 and 481 Hz, corresponding to the ]musical note
In music, a note is the representation of a musical sound.
Notes can represent the pitch and duration of a sound in musical notation. A note can also represent a pitch class.
Notes are the building blocks of much written music: discretizatio ...
s F4, G4, A4, and B4; these notes form an F Lydian Tetrachord.
Seismic vulnerability and improvements
Modern knowledge of the effect of earthquakes on structures led to a program to retrofit
Retrofitting is the addition of new technology or features to older systems. Retrofits can happen for a number of reasons, for example with big capital expenditures like naval vessels, military equipment or manufacturing plants, businesses or go ...
the Golden Gate to better resist seismic events. The proximity of the bridge to the San Andreas Fault
The San Andreas Fault is a continental transform fault that extends roughly through California. It forms the tectonic boundary between the Pacific Plate and the North American Plate, and its motion is right-lateral strike-slip (horizonta ...
places it at risk for a significant earthquake. Once thought to have been able to withstand any magnitude of foreseeable earthquake, the bridge was actually vulnerable to complete structural failure (i.e., collapse) triggered by the failure of supports on the arch over Fort Point. A $392 million program was initiated to improve the structure's ability to withstand such an event with only minimal (repairable) damage. A custom-built electro-hydraulic synchronous lift system for construction of temporary support towers and a series of intricate lifts, transferring the loads from the existing bridge onto the temporary supports, were completed with engineers from Balfour Beatty
Balfour Beatty plc () is an international infrastructure group based in the United Kingdom with capabilities in construction services, support services and infrastructure investments. A constituent of the FTSE 250 Index, Balfour Beatty works acr ...
and Enerpac
The Enerpac business is a division of Actuant (), a $1.5 billion diversified global manufacturing company, and is headquartered in Menomonee Falls, Wisconsin. Enerpac primarily plays in the high-pressure hydraulics market with locations in North ...
, without disrupting day-to-day commuter traffic. Although the retrofit was initially planned to be completed in 2012, it was expected to take several more years.
The former elevated approach to the Golden Gate Bridge through the San Francisco Presidio
The Presidio of San Francisco (originally, El Presidio Real de San Francisco or The Royal Fortress of Saint Francis) is a park and former U.S. Army post on the northern tip of the San Francisco Peninsula in San Francisco, California, and is part o ...
, known as Doyle Drive, dated to 1933 and was named after Frank P. Doyle. Doyle, the president of the Exchange Bank in Santa Rosa and son of the bank's founder, was the man who, more than any other person, made it possible to build the Golden Gate Bridge. The highway carried about 91,000 vehicles each weekday between downtown San Francisco and the North Bay and points north. The road was deemed "vulnerable to earthquake damage", had a problematic 4-lane design, and lacked shoulders; a San Francisco County Transportation Authority study recommended that it be replaced. Construction on the $1 billion replacement, temporarily known as the Presidio Parkway, began in December 2009.
The elevated Doyle Drive was demolished on the weekend of April 27–30, 2012, and traffic used a part of the partially completed Presidio Parkway, until it was switched onto the finished Presidio Parkway on the weekend of July 9–12, 2015. , an official at Caltrans said there is no plan to permanently rename the portion known as Doyle Drive.
Gallery
See also
* 25 de Abril Bridge
The 25 de Abril Bridge ( pt, Ponte 25 de Abril, 25th of April Bridge, ) is a suspension bridge connecting the city of Lisbon, capital of Portugal, to the municipality of Almada on the left (south) bank of the Tagus river. It has a total len ...
, a bridge with a similar design in Portugal
* '' The Bridge'', a 2006 documentary on suicides from the Bridge
* Golden Gate Bridge in popular culture
* List of Historic Civil Engineering Landmarks
* List of longest suspension bridge spans
The world's longest suspension bridges are listed according to the length of their main span (i.e. the length of suspended roadway between the bridge's towers). The length of main span is the most common method of comparing the sizes of suspen ...
* List of San Francisco Designated Landmarks
This is a list of San Francisco Designated Landmarks. In 1967, the city of San Francisco, California adopted Article 10 of the Planning Code, providing the city with the authority to designate and protect landmarks from inappropriate alterations. ...
* List of tallest bridges
* San Francisco–Oakland Bay Bridge
The San Francisco–Oakland Bay Bridge, known locally as the Bay Bridge, is a complex of bridges spanning San Francisco Bay in California. As part of Interstate 80 and the direct road between San Francisco and Oakland, it carries about 260,000 ...
* Suicide bridge
A suicide bridge is a bridge used frequently by people to end their lives, most typically by jumping off and into the water or ground below. A fall from the height of a tall bridge into water may be fatal, although some people have survived jump ...
* Suspension bridge
References
Further reading
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External links
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Bay Area FasTrak
– includes toll information on this and the other Bay Area toll facilities
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* (A documentary film about the construction of the Golden Gate Bridge.)
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* (Educational poster.)
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Bridge
A bridge is a structure built to span a physical obstacle (such as a body of water, valley, road, or rail) without blocking the way underneath. It is constructed for the purpose of providing passage over the obstacle, which is usually somethi ...
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