The Stone Fleet consisted of a fleet of aging ships (mostly whaleships) purchased in New Bedford and other New England ports, loaded with stone, and sailed south during the American Civil War by the Union Navy for use as blockships. They were to be deliberately sunk at the entrance of Charleston Harbor, South Carolina in the hope of obstructing blockade runners, then supplying Confederate interests. Although some sank along the way and others were sunk near Tybee Island, Georgia, to serve as breakwaters, wharves for the landing of Union troops, the majority were divided into two lesser fleets. One fleet was sunk to block the south channel off Morris Island, and the other to block the north channel near Rattlesnake Shoals off the present day Isle of Palms in what proved to be failed efforts