According to the Federal Highway Administration Interstate Highway Route Log and Finder List, Alaska has four Interstate highways that creates a 1,082.22-mile system in the northernmost state. Even though these routes are designated as Interstate highways, they are generally not constructed to Interstate standards and are signed as Alaska State Routes.
Interstate A-3 - Anchorage
Canadian Border - Yukon Territory
Interstate A-1 - Tok Junction
Interstate A-4 - Fairbanks
Interstate A-1 - Anchorage
Interstate A-1 - Palmer
Interstate A-2 - Fairbanks
On December 31, 1981 the Federal Highway Administration approved the addition of the four Alaska Interstates between the following locations:
A-1 from the Alaska-Canada border near Northway west to junction A-2 at Tok Junction, south to junction A-4 near Glennallen and continuing west to junction A-3 at Anchorage.
A-2 from a junction with A-1 at Tok Junction west to junction A-4 and FAP-65 in Fairbanks.
A-3 from a junction with A-1 in Anchorage south and west to junction FAP-21 and FAP-22 in Soldotna via a junction with FAP-31 in the vicinity of Moose Pass.
A-4 from a junction with A-1 near Palmer northwest via Wasilla, Denali National Park and Preserve and Nenana to a junction with A-2 and FAP-65 in Fairbanks.
AASHTO then approved the numbering of the Alaska Interstates on June 28, 1982.1
For more details and pictures, see Oscar Voss's Alaska Interstate Ends. Thanks go to Oscar and Stephen Summers for assisting AARoads with information and constructing this page.