U.S. Route 31
U.S. Numbered Highway in the United States

U.S. Route 31 or U.S. Highway 31 (US 31) is a major north–south U.S. highway connecting southern Alabama to northern Michigan. Its southern terminus is at an intersection with US 90/US 98 in Spanish Fort, Alabama. Its northern terminus is at an interchange with Interstate 75 (I-75) south of Mackinaw City, Michigan.
US 31 once crossed the Straits of Mackinac by car ferry to intersect US 2 north of St. Ignace, Michigan, in the Upper Peninsula and then formerly reached Mackinaw City along the southern approaches of the Mackinac Bridge (which has been taken over by I-75). It also formerly entered downtown Mobile, Alabama, via a long bridge over Mobile Bay.
The southern segment of US 31 connects the cities of Mobile, Montgomery, Birmingham, and Decatur in Alabama, and Nashville in Tennessee. The northern segment of US 31 connects Louisville in Kentucky, and Indianapolis in Indiana. From Nashville to Louisville, US 31 is signed U.S. Route 31W and U.S. Route 31E. From the Mobile Bay area in Alabama to Indianapolis, US 31 travels parallel to Interstate 65 (I-65).
Route description
Alabama
US 31 begins in Spanish Fort, Alabama, at a junction with US 90 and 98.
Begin with the source’s own compact description: “U.S. Route 31” is u.S. Numbered Highway in the United States. The dossier treats that line as a proposition to test through Route, Numbered and Highway, not as a finished interpretation.
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The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Sep 17, 2026. The linked authority identifier is Q409352. VIAF identifies the subject as 315529546. The Library of Congress control number is sh2004009636. Authority coordinates are 32.967, -86.748. 3 of 4 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank.
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This entry incorporates text from “U.S. Route 31” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.