Marlboro -- U.S. County in South Carolina Population (2000): 28818 Housing Units (2000): 11894 Land area (2000): 479.705503 sq. miles (1242.431496 sq. km) Water area (2000): 5.571740 sq. miles (14.430740 sq. km) Total area (2000): 485.277243 sq. miles (1256.862236 sq. km) Located within: South Carolina (SC), FIPS 45 Location: 34.644285 N, 79.668242 W Headwords: Marlboro Marlboro, SC Marlboro County Marlboro County, SC