Fort Collins,city, seat (1868) of Larimer county, northernColorado, U.S. It lies along theCache la Poudre River (the state’s “Trout Route”), in the eastern foothills of theFront Range, at an elevation of 5,004 feet (1,525 metres), 55 miles (89 km) north ofDenver. Thecommunity developed after 1864 around a military outpost named for its commander, Lieutenant William O. Collins of Fort Laramie, Wyoming. The outpost was abandoned in 1872, but the settlement remained and, promoted by atown development company, grew with the arrival of the railroad and a highly successfulsugar beet industry based on local irrigation and stimulated by aland-grant college (nowColorado State University) established there in 1870.

The contemporary city has large lamb-feeding operations and agricultural and quarry-based industries supplemented by tourism and light and high-technology manufactures. The Fort Collins Museum (founded as Pioneer Museum in 1941) preserves in its courtyard the first settler’s cabin and two other historic structures, and it housesmementos of the fort. A portion of the original city centre, including the Avery House, is listed on theNational Register of Historic Places. Fort Collins is the headquarters of the Roosevelt National Forest, a few miles west; the Pawnee National Grassland is to the east. Inc. 1883. Pop. (2010) 143,986; Fort Collins–Loveland Metro Area, 299,630; (2020) 169,810; Fort Collins Metro Area, 359,066.