Olympia is an urban unincorporated area and census-designated place (CDP) in Richland County, South Carolina, United States.

[5] The CDP is in western Richland County, bordered to the north by the city of Columbia, the state capital, and to the west, across the Congaree River, by the city of Cayce.

[6] Four locations in the CDP are listed on the National Register of Historic Places.

Much of the northeast part of the CDP is within the Olympia Mill Village Historic District.

The Olympia Mill is within the Columbia city limits, just north of the CDP.