Greencastle, IN -- U.S. city in Indiana Population (2000): 9880 Housing Units (2000): 3532 Land area (2000): 5.298626 sq. miles (13.723379 sq. km) Water area (2000): 0.046870 sq. miles (0.121392 sq. km) Total area (2000): 5.345496 sq. miles (13.844771 sq. km) FIPS code: 29358 Located within: Indiana (IN), FIPS 18 Location: 39.642297 N, 86.855988 W ZIP Codes (1990): 46135 Note: some ZIP codes may be omitted esp. for suburbs. Headwords: Greencastle, IN Greencastle