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city, seat (1899) of Fergus county, central Montana, U.S. Situated on Big Spring Creek in the dead centre of the state, Lewistown began in 1873 as a trading post on the Carroll Trail. Initially named Reed's Fort for Major A.S. Reed (who opened a post office there in 1881), the town was renamed in 1899 for an earlier officer, Major William H. Lewis, who in 1876 had established a fort 2 miles (3 km) south. After the arrival of the Central Montana (Jawbone) Railroad in 1903, Lewistown became a distribution point for the Judith Basin, once the scene of a gold rush (1880) but now a wheat and cattle district. Its economy has long depended on local mining activities (coal, gold, silver, and gypsum); its industrial output includes oil and cement products. Tourism is of increasing importance because of the city's proximity to the Judith Mountains. A state fish hatchery is 7 miles (11 km) to the east. Inc. 1899. Pop. (1990) 6,051; (2000) 5,813.