Interstate H-201
| Moanalua Freeway | ||||
H-201 highlighted in red | ||||
| Route information | ||||
| Auxiliary route of H-1 | ||||
| Maintained by HDOT | ||||
| Length | 4.1 mi (6.6 km) | |||
| Existed | 1989–present | |||
| History | Signed in 2004 | |||
| NHS | Entire route | |||
| Major junctions | ||||
| West end | Route 99 in Aiea | |||
| H-1 in Aiea H-3 in Halawa | ||||
| East end | H-1 in Honolulu | |||
| Location | ||||
| Country | United States | |||
| State | Hawaii | |||
| Counties | Honolulu | |||
| Highway system | ||||
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Interstate H-201 (H-201, named the Moanalua Freeway) is the only auxiliary Interstate Highway located outside the contiguous United States, serving the island of Oʻahu in the US state of Hawaii. The 4.1-mile-long (6.6 km) loop route connects exits 13 and 19 on H-1, passing Fort Shafter, Tripler Army Medical Center, and the Red Hill Underground Fuel Storage Facility.
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.