South Mountain, TX -- U.S. town in Texas Population (2000): 412 Housing Units (2000): 161 Land area (2000): 1.628916 sq. miles (4.218874 sq. km) Water area (2000): 0.000000 sq. miles (0.000000 sq. km) Total area (2000): 1.628916 sq. miles (4.218874 sq. km) FIPS code: 69120 Located within: Texas (TX), FIPS 48 Location: 31.435056 N, 97.676587 W ZIP Codes (1990): Note: some ZIP codes may be omitted esp. for suburbs. Headwords: South Mountain, TX South Mountain