John Pennekamp Coral Reef State Park

John Pennekamp Coral Reef State Park is a Florida State Park located on Key Largo in Florida. It includes around 70 square nautical miles (240 km2; 93 sq mi) of adjacent Atlantic Ocean waters. The park is roughly 25 miles (40 km) long and extends 3 miles (4.8 km) into the Atlantic Ocean along the prominent Hawk Channel passage. It was the first underwater park in the United States. The park was added to the National Register of Historic Places on April 14, 1972. The primary attractions of the park are the coral reefs (such as Molasses Reef) and their associated marine life. In 2004, the park had more than a million visitors, making it the most popular park in the Florida State Parks system. The Florida Keys and the Flower Garden Banks National Marine Sanctuary in the Gulf of Mexico, near the Texas Gulf Coast, are the only living coral reef formations in the continental United States.