ACE Basin is one of the largest undeveloped estuaries on the East Coast. It's named for the Ashepoo, Combahee and Edisto rivers, which meander past cypress swamps, historic plantation homes, old rice fields and abundant tidal marshes to meet at South Carolina's biologically rich St. Helena Sound. The ACE Basin National Estuarine Research Reserve protects the natural beauty, abundant wildlife and unique cultural heritage of the area. In addition, the reserve preserves habitat for many endangered or threatened species, such as shortnose sturgeon, wood storks, loggerhead sea turtles and bald eagles.