The United States Numbered
Highway System (often called U.S. Routes or
U.S. Highways) is an integrated network of roads and highways numbered
within a nationwide grid in the contiguous United States. As the
designation and numbering of these highways were coordinated among the
states, they are sometimes called Federal Highways, but the roadways
were built and have always been maintained by state or local
governments since their initial designation in 1926.
The route numbers and locations are coordinated by the American
Association of State
Highway and Transportation Officials (AASHTO).
The only federal involvement in AASHTO is a nonvoting seat for the
United States Department of Transportation. Generally, north-to-south
highways are odd-numbered, with lowest numbers in the east, the area
of the founding thirteen states of the United States, and highest in
the west. Similarly, east-to-west highways are typically
even-numbered, with the lowest numbers in the north, where roads were
first improved most intensively, and highest in the south. Major
north–south routes have numbers ending in "1" while major
east–west routes have numbers ending in "0". Three-digit numbered
highways are spur routes of parent highways but are not necessarily
connected to their parents. Some divided routes exist to provide two
alignments for one route, even though many splits have been
Special routes, usually posted with a banner, can provide
various routes, such as an alternate, bypass or business route, for a
Before the U.S. Routes were designated, auto trails designated by auto
trail associations were the main means of marking roads through the
United States. In 1925, the Joint Board on Interstate Highways,
recommended by the American Association of State
(AASHO), worked to form a national numbering system to rationalize the
roads. After several meetings, a final report was approved by the U.S.
Department of Agriculture in November 1925. They received complaints
from across the country about the assignment of routes, so the Board
made several modifications; the U.S.
Highway System was approved in
November 1926. As a result of compromises made to get the U.S. Highway
System approved, many routes were divided, with alignments to serve
different towns. In subsequent years, AASHTO called for such splits in
U.S. Routes to be eliminated.
Expansion of the system continued until 1956, when the Interstate
Highway System was formed. After construction was completed, many U.S.
Routes were replaced by Interstate Highways for through traffic.
Despite the Interstate system, U.S. Highways still form many important
regional connections, and new routes are still being added.
1 System details
1.2 Divided and special routes
2.1 Early auto trails
2.3 Disagreement and refinement, 1925–26
2.4 Expansion and adjustment, 1926–56
2.5 Interstate era, 1956–present
3 The 1925 routes
4 See also
7 Further reading
8 External links
See also: List of United States Numbered Highways
U.S. Route shield
U.S. Route shield is printed on a square blank with a black
California is the only state to use an older cut-out
In general, U.S. Routes do not have a minimum design standard, unlike
the later Interstate Highways, and are not usually built to freeway
standards. Some stretches of U.S. Routes do meet those standards. Many
are designated using the main streets of the cities and towns through
which they run. New additions to the system, however, must
"substantially meet the current AASHTO design standards". As of
1989, the United States Numbered Highways system has a total length of
157,724 miles (253,832 km).
Except for toll bridges and tunnels, very few U.S. Routes are toll
roads. AASHTO policy says that a toll road may only be included as a
special route, and that "a toll-free routing between the same termini
shall continue to be retained and marked as a part of the U.S.
U.S. Route 3
U.S. Route 3 (US 3) meets this obligation;
in New Hampshire, it does not follow tolled portions of the Everett
Turnpike. But US Routes in the system do use parts of four toll
US 51 uses part of the
Jane Addams Memorial Tollway
Jane Addams Memorial Tollway in Illinois;
the old road is
Illinois Route 251.
US 278 uses the tolled Cross Island
Parkway in South Carolina;
the old road is US 278 Business.
US 412 uses the
Cimarron Turnpike in Oklahoma; the old road is
US 412 also uses the
Cherokee Turnpike in Oklahoma; the old road
is Alternate US 412.
The two-digit U.S. Routes follow a simple grid in the contiguous
United States, in which odd-numbered routes run generally north to
south and even-numbered routes run generally east to west.
(US 101 is considered a two-digit route, its "first digit" being
10.) The numbering pattern for U.S. Routes was established first: U.S.
Routes proceed from low even numbers in the north to high even numbers
in the south, and from low odd numbers in the east to high odd numbers
in the west. Numbers ending in 0 or 1 (and US 2), and to a
lesser extent in 5, were considered main routes in the early
numbering, but extensions and truncations have made this distinction
largely meaningless. For example, US 6 was the longest route
until 1964 (that distinction now belongs to US 20).
In the 1950s, the numbering grid for the new Interstate
was established as intentionally opposite from the US grid insofar as
the direction the route numbers increase. Interstate
increase from west-to-east and south-to-north, to keep identically
numbered routes geographically apart in order to keep them from being
confused with one another, and it omits 50 and 60 which would
potentially collide with US 50 and US 60.[c] Both highway
systems still number the routes ending in odd numbers north–south
and the even-numbered highways run east–west, although the
Interstate System labels its main north–south highways with numbers
ending in 5, rather than 1.
In the US
Highway system, three-digit numbers are assigned to spurs of
one or two-digit routes. US 201, for example, splits from
US 1 at Brunswick, Maine, and runs north to Canada. Not all
spurs travel in the same direction as their "parents"; some are
connected to their parents only by other spurs, or not at all, instead
only traveling near their parents. As originally assigned, the first
digit of the spurs increased from north to south and east to west
along the parent; for example, US 60 had spurs, running from east
to west, designated as US 160 in Missouri, US 260 in
Oklahoma, US 360 in Texas, and US 460 and US 560 in New
Mexico. As with the two-digit routes, three-digit routes have been
added, removed, extended and shortened; the "parent-child"
relationship is not always present. For example, several spurs of the
decommissioned US 66 still exist. US 138 exists as a spur of
the former US 38 that US 6 supplanted in
Colorado in the 1930s. US 191 travels from border to border
although its parent, US 91, has been largely replaced by
Interstate 15 (I-15).
In addition, US 163, designated in 1970, is nowhere near
US 63. The short US 57, approved c. 1970, connects to
Highway 57 in Mexico, and lies west of former US 81.
Several routes approved since 1980 do not follow the numbering
US 400, approved in 1994, has no "parent" since there is no
US 0 or US 100.
US 412, approved c. 1982, is nowhere near US 12.
US 425, approved in 1989, is nowhere near US 25.
While AASHTO guidelines specifically prohibit Interstate Highways and
U.S. Routes from sharing a number within the same state (which is
why there are no Interstates 50 or 60), the initial Interstate
numbering approved in 1958 violated this with I-24 and US 24 in
Illinois and I-40, I-80, US 40 and US 80 in California
(US 40 and US 80 were removed from
California in its 1964
Some recent and proposed Interstates, some of them out of place in the
grid, also violate this: I-41 and US 41 in
Wisconsin (which run
concurrently), I-49 and US 49 in Arkansas, I-69 and
US 69 in Texas, and I-74 and US 74 in North Carolina
(which run concurrently).
Some two-digit numbers have never been applied to any U.S. Route,
including 39, 47, 86 and 88.
Divided and special routes
List of divided U.S. Routes
List of divided U.S. Routes and List of special routes
of the United States Numbered
Since 1926, some divided routes were designated to serve related
areas, and designate roughly-equivalent splits of routes. For
instance, US 11 splits into US 11E (east) and US 11W
(west) in Bristol, Virginia, and the routes rejoin in Knoxville,
Tennessee. Occasionally only one of the two routes is suffixed;
US 6N in
Pennsylvania does not rejoin US 6 at its west end.
AASHTO has been trying to eliminate these since 1934; its current
policy is to deny approval of new split routes and to eliminate
existing ones "as rapidly as the State
Highway Department and the
Standing Committee on Highways can reach agreement with reference
Special routes—those with a banner such as alternate or bypass—are
also managed by AASHTO. These are sometimes designated with
lettered suffixes, like A for alternate or B for business.
The official route log, last published by AASHTO in 1989, has been
named United States Numbered Highways since its initial publication in
1926. Within the route log, "U.S. Route" is used in the table of
contents, while "United States Highway" appears as the heading for
each route. All reports of the
Special Committee on Route Numbering
since 1989 use "U.S. Route", and federal laws relating to highways use
"United States Route" or "U.S. Route" more often than the "Highway"
variants. The use of U.S. Route or U.S.
Highway on a local level
depends on the state, with some states such as Delaware using "route"
and others such as Colorado using "highway".
Early auto trails
Main article: Auto trail
Horatio Nelson Jackson
Horatio Nelson Jackson became the first documented person to
drive an automobile from
San Francisco to New York using only a
connection of dirt roads, cow paths, and railroad beds. His journey,
covered by the press, became a national sensation and called for a
system of long distance roads.
In the early 1910s, auto trail organizations—most prominently the
Lincoln Highway—began to spring up, marking and promoting routes for
the new recreation of long-distance automobile travel. While many of
these organizations worked with towns and states along the route to
improve the roadways, others simply chose a route based on towns that
were willing to pay dues, put up signs, and did little else.
Wikisource has original text related to this article:
Report of Joint Board on Interstate Highways October 30, 1925
Wisconsin was the first state in the U.S. to number its highways,
erecting signs in May 1918. Other states soon followed. In 1922 the
New England states got together to establish the six-state New England
Behind the scenes, the federal aid program had begun with the passage
of the Federal Aid
Road Act of 1916, providing 50% monetary support
from the federal government for improvement of major roads. The
Highway Act of 1921 limited the routes to 7% of each
state's roads, while 3 in every 7 roads had to be "interstate in
character". Identification of these main roads was completed in
The American Association of State
Highway Officials (AASHO), formed in
1914 to help establish roadway standards, began to plan a system of
marked and numbered "interstate highways" at its 1924 meeting.
AASHO recommended that the Secretary of Agriculture work with the
states to designate these routes.
Howard M. Gore
Howard M. Gore appointed the Joint Board on Interstate
Highways, as recommended by AASHO, on March 2, 1925. The Board was
composed of 21 state highway officials and three federal Bureau of
Public Roads officials. At the first meeting, on April 20 and 21, the
group chose the name "U.S. Highway" as the designation for the routes.
They decided that the system would not be limited to the federal-aid
network; if the best route did not receive federal funds, it would
still be included. The tentative design for the U.S.
was also chosen, based on the shield found on the Great Seal of
the United States.
The auto trail associations rejected the elimination of the highway
names. Six regional meetings were held to hammer out the details—May
15 for the West, May 27 for the
Mississippi Valley, June 3 for the
Great Lakes, June 8 for the South, June 15 for the North Atlantic, and
June 15 for New England. Representatives of the auto trail
associations were not able to formally address the meetings. However,
as a compromise, they talked with the Joint Board members. The
associations finally settled on a general agreement with the numbering
plans, as named trails would still be included. The tentative system
added up to 81,000 miles (130,000 km), 2.8% of the public road
mileage at the time.
1926 and 1948 versions of the U.S. Route shield
The second full meeting was held August 3 and 4, 1925. At that
meeting, discussion was held over the appropriate density of routes.
William F. Williams of
Massachusetts and Frederick S. Greene of New
York favored a system of only major transcontinental highways, while
many states recommended a large number of roads of only regional
importance. Greene in particular intended New York's system to have
four major through routes as an example to the other states. Many
states agreed in general with the scope of the system, but believed
the Midwest to have added too many routes to the system. The group
adopted the shield, with few modifications from the original sketch,
at that meeting, as well as the decision to number rather than name
the routes. A preliminary numbering system, with eight major
east–west and ten major north–south routes, was deferred to a
numbering committee "without instructions".
After working with states to get their approval, the committee
expanded the highway system to 75,800 miles (122,000 km), or 2.6%
of total mileage, over 50% more than the plan approved August 4. The
skeleton of the numbering plan was suggested on August 27 by Edwin
Warley James of the BPR, who matched parity to direction, and laid out
a rough grid. Major routes from the earlier map were assigned numbers
ending in 0, 1 or 5 (5 was soon relegated to less-major status), and
short connections received three-digit numbers based on the main
highway from which they spurred. The five-man committee met September
25, and submitted the final report to the Joint Board secretary on
October 26. The board sent the report to the Secretary of
Agriculture of October 30, and he approved it November 18, 1925.
Disagreement and refinement, 1925–26
The "final" U.S.
Highway plan as approved November 11, 1926
The new system was both praised and criticized by local newspapers,
often depending on whether that city was connected to a major route.
While the Lincoln
Highway Association understood and supported the
plan, partly because they were assured of getting the US 30
designation as much as possible, most other trail associations
lamented their obsolescence. At their January 14–15, 1926 meeting,
AASHO was flooded with complaints.
In the Northeast, New York held out for fewer routes designated as US
Pennsylvania representative, who had not attended the
local meetings, convinced AASHO to add a dense network of routes,
which had the effect of giving six routes termini along the state
line. (Only US 220 still ends near the state line, and now it
ends at an intersection with future I-86.) Because US 20 seemed
indirect, passing through Yellowstone National Park,
Idaho and Oregon
requested that US 30 be swapped with US 20 to the Pacific
Many local disputes arose related to the committee's choices between
designation of two roughly equal parallel routes, which were often
competing auto trails. At their January meeting, AASHO approved the
first two of many split routes (specifically US 40 between
Manhattan, Kansas and
Limon, Colorado and US 50 between Baldwin
City, Kansas and Garden City, Kansas). In effect, each of the two
routes received the same number, with a directional suffix indicating
its relation to the other. These splits were initially shown in the
log as—for instance—US 40 North and US 40 South, but
were always posted as simply US 40N and US 40S.
The most heated argument, however, was the issue of US 60. The
Joint Board had assigned that number to the Chicago-
Los Angeles route,
which ran more north–south than west–east in Illinois, and then
angled sharply to the southwest to
Oklahoma City, from where it ran
west to Los Angeles.
Kentucky strongly objected to this designated
route, as it had been left off any of the major east-west routes,
instead receiving the US 62 designation. In January 1926, the
committee designated this, along with the part of US 52 east of
Ashland, Kentucky, as US 60. They assigned US 62 to the
Los Angeles route, contingent on the approval of the states
along the former US 60. But
Missouri had already printed maps, and
Oklahoma had prepared
signs. A compromise was proposed, in which US 60 would split at
Springfield, Missouri, into US 60E and US 60N, but both
sides objected. The final solution resulted in the assignment of
US 66 to the Chicago-
Los Angeles portion of the US highway, which
did not end in zero, but was still seen as a satisfyingly round
number. Route 66 came to have a prominent place in popular culture,
being featured in song and films.
With 32 states already marking their routes, the plan was
approved by AASHO on November 11, 1926. This plan included a number
of directionally split routes, several discontinuous routes (including
US 6, US 19 and US 50), and some termini at state
lines. By the time the first route log was published in April
1927, major numbering changes had been made in
Pennsylvania in order
to align the routes to the existing auto trails. In addition, U.S.
Route 15 had been extended across Virginia.
Much of the early criticism of the U.S.
Highway System focused on the
choice of numbers to designate the highways, rather than names. Some
thought a numbered highway system to be cold compared to the more
colorful names and historic value of the auto trail systems. The New
York Times wrote, "The traveler may shed tears as he drives the
Highway or dream dreams as he speeds over the Jefferson
Highway, but how can he get a 'kick' out of 46, 55 or 33 or 21?"
(A popular song later promised, "Get your kicks on Route 66!") The
writer Ernest McGaffey was quoted as saying, "Logarithms will take the
place of legends, and 'hokum' for history."
Expansion and adjustment, 1926–56
This sign, photographed in 1941 on US 99 between Seattle,
Washington, and Portland, Oregon, illustrates one rationale for a
federal highway system: national defense.
When the U.S. numbered system was started in 1925, a few optional
routings were established which were designated with a suffixed letter
after the number indicating "north", "south", "east", or "west". While
a few roads in the system are still numbered in this manner, AASHO
believes that they should be eliminated wherever possible, by the
absorption of one of the optional routes into another route.
In 1934, AASHO tried to eliminate many of the split routes by removing
them from the log, and designating one of each pair as a three-digit
or alternate route, or in one case US 37. AASHO described its
renumbering concept in the October 1934 issue of American
"Wherever an alternate route is not suitable for its own unique
two-digit designation, standard procedure assigns the unqualified
number to the older or shorter route, while the other route uses the
same number marked by a standard strip above its shield carrying the
Most states adhere to this approach. However, some maintain legacy
routes that violate the rules in various ways. Examples can be found
in California, Mississippi, Nebraska, Oregon, and Tennessee. In 1952,
AASHO permanently recognized the splits in US 11, US 19,
US 25, US 31, US 45, US 49, US 73, and
For the most part, the U.S. Routes were the primary means of
inter-city vehicle travel; the main exceptions were toll roads such as
Pennsylvania Turnpike and parkway routes such as the Merritt
Parkway. Many of the first high-speed roads were U.S. Highways: the
Freeway carried US 75, the Pasadena
US 66, and the
Pulaski Skyway carried US 1 and
Interstate era, 1956–present
1961 version of the U.S. Route shield
The Federal Aid
Highway Act of 1956 appropriated funding for the
Highway System, to construct a vast network of freeways
across the country. By 1957, AASHO had decided to assign a new grid to
the new routes, to be numbered in the opposite directions as the U.S.
Highway grid. Though the Interstate numbers were to supplement, rather
than replace, the U.S. Route numbers, in many cases (especially in the
west) the US highways were rerouted along the new Interstates.
Major decommissioning of former routes began with California's highway
renumbering in 1964. The 1985 removal of US 66 is often seen as
the end of an era of US highways.
A few major connections not served by Interstate Highways include
US 6 from Hartford, Connecticut, to Providence, Rhode Island;
US 101 from
Los Angeles to San Francisco; and US 93 from
Phoenix, Arizona to Las Vegas, Nevada. Three state capitals in the
contiguous U.S. are served only by U.S. Routes: Dover, Delaware;
Jefferson City, Missouri; and Pierre, South Dakota.
In 1995 the National
Highway System was defined to include both the
Highway System and other roads designated as important to
the nation's economy, defense, and mobility.
AASHTO is in the process of eliminating all intrastate U.S. Highways
less than 300 miles (480 km) in length "as rapidly as the State
Highway Department and the Standing Committee on Highways of the
American Association of State Highway and Transportation Officials
American Association of State Highway and Transportation Officials can
reach agreement with reference thereto". New additions to the system
must serve more than one state and "substantially meet the current
AASHTO design standards". A version of this policy has been in
place since 1937.
The 1925 routes
The original major transcontinental routes in 1925, along with the
auto trails which they roughly replaced, were as follows:
US 1, Fort Kent, Maine, to Miami, Florida: Atlantic Highway
US 11, Rouses Point, New York, to New Orleans, Louisiana
US 21, Cleveland, Ohio, to
Jacksonville, Florida (where it met
US 31, Mackinaw City, Michigan, to Mobile, Alabama
US 41, Copper Harbor, Michigan, to Tampa, Florida: Dixie Highway
US 51, Hurley, Wisconsin, to New Orleans, Louisiana
US 61, Canadian border north of Grand Marais, Minnesota, to New
US 71, International Falls, Minnesota, to Baton Rouge, Louisiana
(where it met US 61): Jefferson Highway
US 81, Canadian border north of Pembina, North Dakota, to Laredo,
Texas: Meridian Highway
US 91, Great Falls, Montana, to south of Las Vegas, Nevada
US 101, Port Angeles, Washington, to San Diego, California:
US 2, Houlton, Maine, to Bonners Ferry, Idaho
US 10, Detroit, Michigan, to Seattle, Washington: National Parks
US 20, Boston, Massachusetts, to Newport, Oregon
US 30, Atlantic City, New Jersey, to Astoria, Oregon: Lincoln
US 40, Atlantic City, New Jersey, to San Francisco, California:
US 50, Annapolis, Maryland, to
Wadsworth, Nevada (where it met
US 60, Chicago, Illinois, to Los Angeles, California
US 70, Morehead City, North Carolina, to
Holbrook, Arizona (where
it met US 60)
US 80, Savannah, Georgia, to San Diego, California: Dixie
Jacksonville, Florida to Van Horn, Texas, (where it met
US 80): Old Spanish Trail
US 10, US 60, and US 90 only ran about two thirds of
the way across the country, while US 11 and US 60 ran
significantly diagonally. US 60's violation of two of the
conventions would prove to be one of the major sticking points;
US 60 eventually was designated as US 66 in 1926, and later
it became popular in the culture. US 101 continues east and then
south to end at Olympia, Washington. The western terminus of
US 2 is now at Everett, Washington.
U.S. Roads portal
Highway System (United States)
New England road marking system
United States Numbered Bicycle Routes
^ The American Association of State
Highway Officials (AASHO) was
renamed the American Association of State
Highway and Transportation
Officials (AASHTO) on November 11, 1973.
^ As of 1989[update].
^ Exceptions to this rule do occur. Both US 24 and I-24 exist
within the state of Illinois, and more recently, I-41 was designed on
top of US 41 in Wisconsin.
^ a b c d e f g h i j k l m n o Weingroff, Richard F. (April 7, 2011).
"From Names to Numbers: The Origins of the US Numbered Highway
Highway History. Federal
Highway Administration. Retrieved
June 10, 2011.
Highway Administration (December 4, 2012). "November 13".
Highway History. Federal
Highway Administration. Retrieved August 18,
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Special Committee on U.S. Route Numbering (1989). United
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Highway and Transportation Officials. p. iv. Archived from
the original (PDF) on January 1, 2014. Retrieved March 16, 2012.
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p. 83, §§ D15, D19; p. 92, § J8. ISBN 0-528-00626-6.
^ "Ask the Rambler: What Is The Longest
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^ Arizona Department of Transportation. "Arizona DOT Right-of-Way
Resolutions". Arizona Department of Transportation. Retrieved March
^ American Association of State
Highway and Transportation Officials
(January 2000). "Establishment of a Marking System of the Routes
Comprising the National System of Interstate and Defense Highways"
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^ "Ross (AR04) Newsletter—Interstate 49". Congressman Mike Ross.
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Texas Department of Transportation. "I-69/TTC (Northeast
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^ Woodard, Johnny (October 8, 2008). "I-74 four-lane to Lumberton
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^ a b c d Weingroff, Richard F. (April 7, 2011). "US 11 Rouses
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^ For example, compare the following for an alternate route in Ohio:
Ohio Department of Transportation
Ohio Department of Transportation Office of Technical Services,
GIS/Mapping Section (2011). Official Transportation Map (Map).
1:570,240. Columbus: Ohio Department of Transportation. §§
Google (May 5, 2013). "Street View of US 20A/SR 15 near
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Route", "United States Highway" and "U.S. Highway"
Delaware Department of Transportation
Delaware Department of Transportation (2006). "2006 Traffic Count
and Mileage Report" (PDF). Delaware Department of Transportation.
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^ Colorado Department of Transportation. "Segment Descriptions for
Highway 006". Colorado Department of Transportation. Retrieved June
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^ "Motor Sign Uniformity". The New York Times. April 16, 1922.
^ McNichol (2006), p. 67.
^ McNichol (2006), p. 121.
^ a b
Bureau of Public Roads
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^ Weingroff, Richard F. (April 7, 2011). "US 22: The William Penn
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^ "United States Numbered Highways". American Highways. American
Association of State
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^ McNichol (2006), p. 78.
^ Feldstein, Dan (June 27, 1999). "A rare quiet interlude for area's
first freeway/ Next major upgrade: Causeway in 2002". Houston
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^ Correspondence between the Division of Highways and American
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California Highways. Retrieved June 10, 2011. [unreliable
Rand McNally (1946).
Road Atlas (Map). Scale not given. Chicago:
Rand McNally. p. 42. New York and Vicinity inset.
^ "Route Renumbering: New Green Markers Will Replace Old Shields".
California Highways and Public Works. 43 (3–4): 11–13.
March–April 1964. ISSN 0008-1159. Retrieved June 10,
^ "New Signing Policy on U.S. Routes".
California Highways and Public
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Ingram, Tammy (2014). Dixie Highway:
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