Johnsonville crater, also known as the Snow's Island crater, is a proposed impact structure in South Carolina where the Lynches and Pee Dee rivers meet. About 8 miles across, it appears as a circular geophysical feature rather than an obvious surface landform. Researchers first identified it through magnetic anomalies and later examined it with well-drilling cores, which reportedly contained impact breccia. Snow's Island has been interpreted as the central uplift created after the impact. Its classification remains disputed, however, with the Russian Academy of Sciences treating it as a proven impact crater while the Earth Impact Database does not confirm it.