Sewee Mound, Archaeological site in Charleston County, United States

Sewee Mound, also called the Old Fort, is a prehistoric shell ring near Awendaw, South Carolina. It averages 149 feet (about 45 m) in diameter and stands 10 feet (about 3 m) high, built up largely of oyster shell, with a smaller midden nearby.

Sewee Mound was listed on the National Register of Historic Places in 1970. It is one of 20 or more prehistoric shell rings found from the central coast of South Carolina to the central coast of Georgia.

Sewee Mound is also called the Old Fort, a name that recalls later use of the shell ridge rather than its prehistoric origin. The mound itself is largely oyster shell, the food waste of the people who built the ring, and a smaller midden lies nearby.

Sewee Mound lies near Awendaw, off U.S. Route 17, within Francis Marion National Forest. The shell ring and the smaller nearby midden sit on forest ground; no visitor facilities are on site. Check the forest's own trail and access information before setting out, and keep to established paths so the oyster-shell deposits are not trampled.

This shell ring belongs to a group of about twenty similar structures scattered along a specific stretch of coast between central South Carolina and Georgia. The concentration of these ancient rings in this narrow band makes it a key location for understanding how early coastal peoples organized their settlements.