|Established in 1963, John Pennekamp Coral Reef State Park was the first undersea park in the United States. John Pennekamp Coral Reef State Park, and the adjacent Florida Keys National Marine Sanctuary, cover approximately 178 nautical square miles of coral reefs, seagrass beds and mangrove swamps. The park extends 3 miles into the Atlantic Ocean and is approximately 25 miles in length. These areas were established to protect and preserve a portion of the only living coral reef in the continental United States. The park was added to the National Register of Historic Places on April 14, 1972.
The park named for the late John D. Pennekamp, a Miami newspaper editor, whose efforts contributed to the establishments of Everglades National Park and the preservation of what would become John Pennekamp Coral Reef State Park.
The park contains a wide variety of tropical vegetation, shore birds and marine life. While the mangrove swamps and tropical hammocks offer visitors a unique and interesting experience, it is the coral formations and associated marine life that most park visitors come to enjoy. The coral reef at John Pennekamp Coral Reef State Park are among the most beautiful and diverse of all living communities.