As soon as you step into the waters of the Florida Keys, you have entered Florida Keys National Marine Sanctuary. Within the boundaries of this sanctuary lie unique and important marine resources, including North America's only coral barrier reef, extensive seagrass beds, mangrove-fringed islands, and more than 6,000 species of marine life. The sanctuary also protects pieces of our nation's history such as shipwrecks and other archeological treasures. This complex marine ecosystem is the foundation for the tourism and commercial fishing based economies that are vital to Florida. Florida Keys National Marine Sanctuary is a great place to explore these cherished waters through diving, snorkeling, boating, and kayaking. To learn more about this sanctuary, visitors should stop by the Florida Keys Eco-Discovery Center in Key West, Florida.

The water surrounding the group of islands is formed by the Florida Keys. The sanctuary is south of Miami and stretches westward to encompass the Dry Tortugas (excluding Dry Tortugas National Park).