U.S. Route 91
U.S. Numbered Highway in Utah and Idaho in the United States
U.S. Route 91 or U.S. Highway 91 (US 91) is a 172.7-mile-long (277.9 km) north–south United States highway running from Brigham City, Utah, to Idaho Falls, Idaho, in the U.S. states of Idaho and Utah. Despite the "1" as the last digit in the number, US 91 is no longer a cross-country artery, as it has mostly been replaced by Interstate 15. The highway currently serves to connect the communities of the Cache Valley to I-15 and beyond. Prior to the mid-1970s, US 91 was an international commerce route from Long Beach, California, to the Canada–US border north of Sweetgrass, Montana. US 91 was routed on the main streets of most of the communities it served, including Las Vegas Boulevard in Las Vegas and State Street in Salt Lake City. From Los Angeles to Salt Lake, the route was built along the corridor of the Arrowhead Trail. A portion of the highway's former route in California is currently State Route 91.
Route description
Utah
US 91 begins at Brigham City. The highway was originally routed through Brigham City, but today runs on a southern bypass (locally designated 1100 South). The original routing is now State Route 90.
The public source identifies “U.S. Route 91” as u.S. Numbered Highway in Utah and Idaho in the United States. This brief keeps that definition visible, then builds a research path around Route, Numbered and Highway.
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A short description can identify a subject without explaining its stakes. For “U.S. Route 91”, the useful work is to connect “u.S. Numbered Highway in Utah and Idaho in the United States” to the records capable of establishing context and consequence.
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 Jan 18, 2026. The linked authority identifier is Q410767. Authority coordinates are 42.812, -112.221. 2 of 2 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1100.
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This entry incorporates text from “U.S. Route 91” 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.