What is the name of the largest coral reef in the continental United States?

The largest coral reef in the continental United States is the Florida Reef. Also called the Florida Reef Tract or Great Florida Reef, it follows the seaward edge of the Florida Keys and is the only living coral barrier reef in the continental United States.

The reef extends roughly 270 kilometers, from the area near Fowey Rocks east of Key Biscayne to the Marquesas Keys. It lies a few miles offshore, generally along the 20-meter depth contour, and includes more than 6,000 individual reefs. Its warm, clear waters support hundreds of fish and marine-mammal species, as well as dozens of stony and soft coral species.

A common mix-up is Dry Tortugas, which is part of the broader Florida Keys reef region and contains important reefs, but is not the name of the entire system. The reef is also different from the Great Barrier Reef, the world’s largest coral reef system, which lies off Australia.