Marine Corps Base Camp Lejeune is a 246-square-mile (640 km2) United States military training facility in Jacksonville, North Carolina. Its 14 miles (23 km) of beaches make the base a major area for amphibious assault training, and its location between two deep-water ports allows for fast deployments. The main base is supplemented by six satellite facilities: Marine Corps Air Station New River, Camp Geiger, Stone Bay, Courthouse Bay, Camp Johnson, and the Greater Sandy Run Training Area. The Marine Corps port facility is in Beaufort, at the southern tip of Radio Island. It is occupied only during military port operations.