Cross Keys is an unincorporated community in Union County, South Carolina. Historically, it was the site of the "large and prosperous" Cross Keys plantation. A post office was established at Cross Keys in 1809 and operated until 1909. Cross Keys House, the plantation house built in 1812–1814, stood at the intersection of two important early highways (the old Charleston Road, now known as Old Buncombe Road, and Old Ninety-Six Road, also known as the Old Piedmont Stage Road) and was a stop for early travelers. It is listed on the National Register of Historic Places.
Coordinates: 34°37′55″N 81°46′35″W / 34.63194°N 81.77639°W