Interstate H-201

Interstate H-201 (H-201) is the only auxiliary Interstate located outside the Contiguous United States, on the island of O‘ahu in the U.S. state of Hawaii. 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, Tripler Army Medical Center, and Red Hill. The highway is 4.1 miles (6.6 km) long.

Moanalua Freeway
Route information
Auxiliary route of
Length	4.10 mi (6.60 km)
Existed	1989–present
History	Signed in 2004
Major junctions
West end	in Aiea
Major intersections	in Hālawa
East end	in Honolulu
Highway system
Interstate Highway System Main Auxiliary Suffixed Business Future Routes in Hawaii
← →

Despite being designated an Interstate in 1989, until mid-2004 the route was an unsigned Interstate, signed only as Route 78.

H-201 eastbound approaching Exit 3 in Moanalua. Letters in H-201 shields require thinner text, such as on signage like this one.