U.S. Route 12
U.S. Numbered Highway in the United States
U.S. Route 12 or U.S. Highway 12 (US 12) is an east–west United States Numbered Highway, running from Aberdeen, Washington, to Detroit, Michigan, for almost 2,500 miles (4,000 km). The highway has mostly been superseded by Interstate 90 (I-90) and I-94, but, unlike most U.S. Highways that have been superseded by an Interstate, US 12 remains intact as an important link for local and regional destinations. The highway's western terminus in Aberdeen is at an intersection with US 101, while the highway's eastern terminus in Downtown Detroit is at the corner of Michigan and Cass avenues, near Campus Martius Park.
Route description
Washington
The western terminus of US 12 is located in Aberdeen. The highway loosely follows the eastbound leg of the Lewis and Clark Expedition, between Wallula and Clarkston, thus being marked as part of the Lewis and Clark National Historic Trail. The east end of the highway in the state is at Clarkston, where the highway crosses the Snake River into Idaho at Lewiston, Idaho.
The Washington section of US 12, other than a concurrency with I-5, is defined at Washington Revised Code § 47.17.055.
Idaho
US 12 enters the state at Lewiston, crossing the Snake River from Clarkston, Washington. It ascends the Clearwater River, running concurrently with US 95 for seven miles (11 km). It reduces to a two-lane undivided highway with signs that read "winding road next 99 miles [159 km]" and goes on to Orofino, continuing up the middle fork of that river to Lowell, the junction of the Lochsa and Selway rivers.
The public source identifies “U.S. Route 12” as u.S. Numbered Highway in the United States. This brief keeps that definition visible, then builds a research path around Route, Numbered and Highway.
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Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Sep 20, 2026. The linked authority identifier is Q407564. VIAF identifies the subject as 315528845. The Library of Congress control number is sh2001005642. 3 of 3 selected statements include explicit references; 1 carry qualifiers and 0 use preferred rank.
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This entry incorporates text from “U.S. Route 12” 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.