Redbird Reef is an artificial reef located in the Atlantic Ocean, off the coast of Slaughter Beach, Delaware, 16 miles (25.7 km) east of the Indian River Inlet. Established by the in 2001, this reef covers 1.3 square nautical miles of ocean floor and is located 80 feet (24.4 m) below the surface. The reef comprises 714 Redbird (R26–R36 series) New York City Subway cars dumped by Weeks Marine, 86 retired tanks and armored personnel carriers, eight tugboats and barges, and 3,000 tons of ballasted truck tires. The amount of marine food has increased 400 times over 7 years.