John Pennekamp Coral Reef State Park on Key Largo protects about 70 square nautical miles of Atlantic waters and became the first underwater park in the United States. Created after decades of concern over damage from collecting coral and marine life for tourists, it grew from preservation efforts led by Gilbert L. Voss and John D. Pennekamp. Florida set aside the state-controlled reefs, and a neighboring federal reef preserve followed in 1960; the park opened in 1963 and was later renamed for Pennekamp. Its living reefs, rare in the continental United States, make it important both for recreation and for conservation.