The Hawaii Department of Transportation maintains the smallest state-maintained system of state highways in the country. It consists of Interstates, state highways, and secondary state highways, totaling approximately .

The state's four Interstates, all located on Oahu, are built to mainland standards unlike their counterparts in Alaska and Puerto Rico. The first three routes (H-1, H-2, and H-3) were approved in 1960, while an auxiliary route (H-201) was added in 1989.

Primary and auxiliary interstates

The Interstate Highway System was extended to Hawaii on August 29, 1960, a year after statehood, when the Bureau of Public Roads approved three routes—H-1, H-2, and H-3—for addition to the Interstate network. A fourth route, H-201, was later added in 1989 as an auxiliary designation for part of the Moanalua Freeway.

Unlike most Interstates on the mainland, whose primary purpose is civilian travel and interstate commerce, Hawaii's Interstates were built specifically to serve national defense needs by linking the island's scattered military installations. H-1 connects the Pearl Harbor naval complex and Hickam Air Force Base to a naval ammunition storage facility and the former Fort Ruger base at Diamond Head; H-2 connects to Schofield Barracks and Wheeler Army Airfield; and H-3 connects to Marine Corps Base Hawaii at Kāneʻohe Bay.

H-3 illustrates this defense purpose most directly. It satisfies the national defense purpose of connecting Marine Corps Base Hawaii with the US Navy port at Pearl Harbor via H-1, and opened on December 12, 1997 specifically to connect military personnel stationed across the island, linking the naval base at Pearl Harbor to the Marine Corps base on Oʻahu's northeast coast. Much of the early push for building H-3 came from the military itself, which had faced difficulties moving troops across Oʻahu.

Primary and secondary routes The current state (then territorial) highway numbering system was established in 1955. Route numbers are organized so that the initial digit corresponds to the island: Numbers beginning with 1 or 2: Hawaiʻi Numbers beginning with 3: Maui Numbers beginning with 4: Molokai, Lanai Numbers beginning with 5: Kauai Numbers beginning with 6 to 9: Oahu

In general, two-digit numbers are primary highways, maintained by the state. Three-digit routes are typically secondary arterials or collectors, while four-digit routes are typically collectors and minor roads. For secondary routes, the first two digits generally relate to the associated primary route. Many secondary routes are county-maintained and unsigned, their route numbers being used merely by state agencies as an asset-tracking measure.

When referring to highways, Hawaiʻi residents usually refer to state highways by their names instead of their route numbers (e.g. Kamehameha Highway instead of Route 99). Note that one named highway may encompass several route numbers (e.g. Kamehameha Highway, which carries Routes 80, 83, 99, and 830 at various points along its length) and vice versa.

Numbered county routes

Temporary Federal routes During World War II, a temporary Federal route numbering system was set up on the island of Oahu. They were used to assist military personnel not accustomed to the Hawaiian street names during the time of Martial law in the Territory of Hawaii from 1941 to 1945. Though marked with U.S. Route shields, they were never part of the United States Numbered Highway System.

Number Length (mi) Length (km) Southern or western terminus Northern or eastern terminus Formed Removed Notes Route 1 — — Route 2 / Route 13 in Honolulu Route 2 / Route 223 near Waialua 1941 1945 South Vineyard Boulevard » Wai‘alae Avenue » Kalaniana‘ole Highway » Kailua Road » Oneawa Street » Mōkapu Boulevard » Kāne‘ohe Bay Drive » Kamehameha Highway Route 2 — — Route 1 / Route 13 in Honolulu Route 1 / Route 223 near Waialua 1941 1945 Nimitz Highway » Kamehameha Highway Route 13 — — Route 1 / Route 2 in Honolulu Route 1 in Kailua 1941 1945 Bishop Street » Pali Highway Route 220 — — Route 223 in Nānākuli Route 2 in Pearl City 1941 1945 Farrington Highway Route 223 — — Route 220 in Nānākuli Route 1 / Route 2 near Waialua 1941 1945 Farrington Highway (road permanently closed at Ka‘ena Point) Route 230 — — Route 1 in Kāneohe Route 1 in Kailua 1941 1945Kailua Road » Oneawa Street » Mōkapu Boulevard » Kāne‘ohe Bay Drive

See also

References

External links AARoads Hawaii Highways Page Hawaii Highways