Monitor National Marine Sanctuary is the site of the wreck of the USS Monitor, one of the most famous shipwrecks in U.S. history. It was designated as the country's first national marine sanctuary on January 30, 1975, and is one of only two of the sixteen national marine sanctuaries created to protect a cultural resource rather than a natural resource. The sanctuary comprises a column of water 1 nautical mile (1.9 km) in diameter extending from the ocean’s surface to the seabed around the wreck of the Civil War ironclad, which lies 16 nautical miles (30 km) south-southeast of Cape Hatteras, North Carolina. Average water depth in the sanctuary is 230 feet (70 m). Since its sinking in 1862, the Monitor has become an artificial reef attracting numerous fish species, including amberjack, black sea-bass, oyster toadfish and great barracuda.