Interstate Highway
The Dwight D. Eisenhower National System of Interstate and Defense Highways, commonly known as the Interstate Highway System, is a network of controlled-access highways that forms part of the National Highway System in the United States. Th ...
located outside the
Contiguous United States
The contiguous United States (officially the conterminous United States) consists of the 48 adjoining U.S. states and the Federal District of the United States of America. The term excludes the only two non-contiguous states, Alaska and Hawaii ...
, serving the island of O‘ahu in the U.S. state of
Hawaii
Hawaii ( ; haw, Hawaii or ) is a state in the Western United States, located in the Pacific Ocean about from the U.S. mainland. It is the only U.S. state outside North America, the only state that is an archipelago, and the only stat ...
. The H-201 designation is also known as the Moanalua Freeway. The loop route connects exits 13 and 19 on H-1, passing
Fort Shafter
Fort Shafter, in Honolulu CDP, Page 4/ref> City and County of Honolulu, Hawai‘i, is the headquarters of the United States Army Pacific, which commands most Army forces in the Asia-Pacific region with the exception of Korea. Geographically, Fort ...
,
Tripler Army Medical Center
Tripler Army Medical Center (TAMC) is a major United States Department of Defense medical facility administered by the United States Army in the state of Hawaii. It is the tertiary care hospital in the Pacific Rim, serving local active and retire ...
, and Red Hill.
Despite being designated an Interstate in 1989, until mid-2004 the route was an unsigned Interstate, signed only as Route 78. The section of the Moanalua Freeway between Route 99 (Kamehameha Highway) and the western H-1 interchange remains designated as Route 78.
Downtown Honolulu
Downtown Honolulu is the current historic, economic, and governmental center of Honolulu, the capital and largest city of the U.S. state of Hawaii. It is bounded by Nuuanu Stream to the west, Ward Avenue to the east, Vineyard Boulevard to the nor ...
, traveling on the Moanalua Freeway around the northeast side of
Salt Lake
A salt lake or saline lake is a landlocked body of water that has a concentration of salts (typically sodium chloride) and other dissolved minerals significantly higher than most lakes (often defined as at least three grams of salt per litre). ...
. It begins at a junction with Route 99 on the north side of
Aloha Stadium
Aloha Stadium is a closed multi-purpose stadium located in Halawa, Hawaii, a western suburb of Honolulu (though with a Honolulu address). It is the largest stadium in the state of Hawaii. , the stadium ceased fan-attended operations indefinitely ...
, located near
Joint Base Pearl Harbor–Hickam
Joint Base Pearl Harbor–Hickam (JBPHH) is a United States military base on the island of Oahu, Hawaii. It is Joint Base, an amalgamation of the United States Air Force's Hickam Air Force Base and the United States Navy's Naval Station Pearl ...
. The freeway travels east through an interchange with H-1, which continues west towards Kapolei and south to
Daniel K. Inouye International Airport
Daniel K. Inouye International Airport , also known as Honolulu International Airport, is the main airport of Oahu, Hawaii.H-3. H-201 and H-3 briefly run parallel to each other through
Halawa
Halawa () is a census-designated place (CDP) in the ‘Ewa District of Honolulu County, Hawaii, United States. Halawa Stream branches into two valleys: North and South Halawa; North Halawa is the larger stream and fluvial feature. Their conflue ...
, where the former intersects Kahuapaani Street, before H-3 splits to continue northeast across the Koʻolau Range. H-201 turns southeast to avoid Red Hill and travels through
Moanalua
Moanalua is a valley, a stream, an ahupuaa, and a residential neighborhood in Honolulu, Hawaii. The valley extends inland from behind Āliapaakai crater (Salt Lake) to the crest of the Koʻolau Range.
Neighboring areas include Māpunapuna and S ...
, a residential neighborhood with hospitals operated by
Kaiser Permanente
Kaiser Permanente (; KP), commonly known simply as Kaiser, is an American integrated managed care consortium, based in Oakland, California, United States, founded in 1945 by industrialist Henry J. Kaiser and physician Sidney Garfield. Kaiser P ...
, the
Department of Veteran Affairs
Veterans' affairs is an area of public policy concerned with relations between a government and its communities of military veterans. Some jurisdictions have a designated government agency or department, a Department of Veterans' Affairs, Minist ...
Tripler Army Medical Center
Tripler Army Medical Center (TAMC) is a major United States Department of Defense medical facility administered by the United States Army in the state of Hawaii. It is the tertiary care hospital in the Pacific Rim, serving local active and retire ...
). The freeway continues southeast, passing Moanalua Gardens and an industrial area, before it bisects
Fort Shafter
Fort Shafter, in Honolulu CDP, Page 4/ref> City and County of Honolulu, Hawai‘i, is the headquarters of the United States Army Pacific, which commands most Army forces in the Asia-Pacific region with the exception of Korea. Geographically, Fort ...
, a military installation in the
Kalihi Valley
Kalihi is a neighborhood of Honolulu on the island of Oʻahu in Hawaiʻi, United States. Split by the Likelike Highway (Route 63), it is flanked by downtown Honolulu to the east and Mapunapuna, Moanalua and Salt Lake to the west.
Kalihi is the ...
. H-201 then terminates on the south side of Fort Shafter at an interchange with H-1, which continues southeast towards Downtown Honolulu on the Lunalilo Freeway.
The freeway is maintained by the
Hawaii Department of Transportation
The Hawaii Department of Transportation (HDOT) is a state government organization which oversees transportation in the U.S. state of Hawaii. The agency is divided into three divisions dealing with aviation, maritime, and roads.
HDOT Divisions Ai ...
(HDOT) and is designated as part of the National Highway System, a network of strategic highways in the United States. H-201 is generally six to eight lanes wide with an eastbound high-occupancy vehicle lane during the morning
rush hour
A rush hour (American English, British English) or peak hour (Australian English) is a part of the day during which traffic congestion on roads and crowding on public transport is at its highest. Normally, this happens twice every weekday: on ...
from Halawa to Puuloa Road. Traffic volumes on the highway, measured in terms of annual average daily traffic, ranged in 2020 from a minimum of 19,800 vehicles at its western terminus to a maximum of 136,100 vehicles near H-3.
History
Moanalua Road, the direct predecessor to H-201, was an unpaved road constructed in the late 19th century to connect Honolulu's King Street to Aiea. The road was macadamized in 1899 but remained in poor condition for several years, prompting calls to prioritize its improvement for tourists. It was repaired in the 1910s, following the establishment of Fort Shafter, and plans were announced to straighten sections of the road in 1921.
The territorial government began preliminary construction of a four-lane divided highway to replace Moanalua Road in 1948, following the opening of the new Tripler Army Hospital. The project, which would reduce the number of curves on the road from 24 to 6, was also meant to connect with the Mauka Arterial (now part of H-1) and relieve congestion on the
Kamehameha Highway
Kamehameha Highway is one of the main highways serving suburban and rural O‘ahu in the U.S. state of Hawai‘i. Informally known as Kam Highway, it begins at Nimitz Highway near Pearl Harbor and Hickam Air Force Base in Honolulu, serves the is ...
near Pearl Harbor. The westernmost of the divided highway was dedicated and opened to traffic on April 28, 1954. The road was designated as part of Route 72 in 1955.
The remaining section of the original Moanalua Road, bisecting Fort Shafter, was upgraded to a divided highway in the second phase and end at an interchange with the Lunalilo Freeway (also part of H-1). With funding from the territorial highway department and approval of the U.S. Army, several facilities at Fort Shafter were relocated to new buildings in 1958 and the former Tripler Army Hospital was demolished in May 1959 to make way for the project. Construction began in June 1959 under a $1.46 million contract awarded to Hawaiian Dredging and Construction. The widened Fort Shafter section of the Moanalua Highway was opened in September 1960, featuring an interchange at E Street and several overpasses.
Plans to upgrade the western terminus at Aiea to an interchange with the Kamehameha Highway were approved in the late 1950s. Construction began in 1960 and the Aiea interchange opened in stages between June 1965 and November 1965, at a cost of $2 million. A western extension of the Moanalua Highway from the Aiea interchange with flyover ramps to connect to the Kamehameha Highway was approved for construction in 1964 and was opened to traffic in June 1966. The interchange with the Lunalilo Freeway at the eastern end of the highway was completed in May 1964.
The conversion of the highway to a full freeway began in September 1971 with work near Red Hill and was completed in August 1974. It was estimated to cost $37 million total to construct. An eastbound lane between Halawa and Puuloa Road was designated for
carpools
Carpooling (also car-sharing, ride-sharing and lift-sharing) is the sharing of 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 people usi ...
of four or more people in October 1974. The highway was designated as Route 78 in the early 1970s.
The Federal Highway Administration approved the addition of H-201 to the Interstate Highway System on November 1, 1989. HDOT requested that the Moanalua Freeway be reclassified as an Interstate so that the interchange with H-1 at the eastern end could conform to federal highway standards. HDOT originally asked the
American Association of State Highway and Transportation Officials
The American Association of State Highway and Transportation Officials (AASHTO) is a standards setting body which publishes specifications, test quality control, protocols, and guidelines that are used in highway design and construction through ...
(AASHTO) in June 1990 to approve the freeway as H-1A in an application to AASHTO's Special Committee on U.S. Route Numbering, the committee which approves Interstate Highway designations. HDOT resubmitted a request later that year to number it as H-101, and AASHTO approved it as H-201 on December 8, 1990. The highway was initially designated H-1A, but AASHTO policy does not generally allow alphabetic suffixes in Interstate numbers. The final designation, H-201, conforms to the general rule for three-digit Interstate loop routes that uses an even initial digit.
Until 2004, the state Department of Transportation chose not to sign H-201 as such, instead retaining the designation Route 78. Reasons given included the following:
* inability to render the new route number in a legible manner (because it has four characters, longer than the one to three characters of any other Interstate, it is necessary to use the thinnest font to render the number, and the shield is wider than the standard Interstate shield)
* encouraging motorists to use the newer and better designed H-1
* avoiding confusion with
Interstate H-2
Interstate H-2 (H-2, named the Veterans Memorial Freeway) is an intrastate Interstate Highway located on the island of O‘ahu in the U.S. state of Hawai‘i. The north–south freeway connects H-1 in Pearl City to Mililani and Wahiawā, whe ...
In July 2004, in conjunction with a major resurfacing of both sides of the freeway, it was decided to bring the signage in line with the official designation.