The islands of Marathon and the Middle Keys have a vast network of coral reefs, shipwrecks, and patch reefs that offer truly outstanding snorkeling and diving. Sombrero Reef is considered one of the most beautiful dive spots in the world, and its many shipwrecks and patch reefs are teeming with life. Marathon is often called the heart of the Florida Keys, and its stunning reefs and abundant marine life help it live up to its nickname.
Sombrero Reef
When the subject of scuba diving comes up in Marathon, the first place anyone thinks of is Sombrero Reef, and for good reason. Eight miles offshore, the reef is marked by a 142 foot lighthouse that still functions today. But the best sightseeing is beneath the water. Stunning coral formations-gorgonians, brain corals, lettuce coral, stag coral and finger coral provide a colorful home to thousands of brightly colored tropical fish, southern stingrays, nurse sharks, crustaceans and more. Giant barracuda silently hover near the lighthouse moorings. With depths ranging from 5 to 35 feet, Sombrero Reef is perfect for snorkelers and divers of all skill levels.
Delta Shoals
The Delta Shoals are a half-mile long stretch of coral canyons and shipwrecks that are teeming with sea life. Brain coral, elkhorn coral, and star coral dominate in the calm clear water here-perfect for diving and snorkeling alike.
Coffin's Patch
Coffin's Patch is a quiet collection of six distinct patch reefs that extends for 1.5 miles southeast of Key Colony Beach. Each patch reef has a different predominant coral species-elkhorn on one, pillar coral on another for example-and includes many rare and indigenous coral species. The shallow depths and minimal water traffic make Coffin's Patch an excellent snorkeling location.
Adelaide Baker
The Adelaide Baker is a 153 foot ship that sunk in 1889 off of Duck Key. Scattered over a quarter-mile area, the remains of the Adelaide Baker have become home to many colorful corals and fish species. Two huge steam stacks are the most striking feature of the wreck and at a depth of just 25 feet; the Adelaide Baker is a great historic location for both snorkeling and diving.
The Thunderbolt
The Thunderbolt is a 188 foot naval ship that was intentionally sunk in 1986 to form an artificial reef. The hull, which sits upright at a depth of 115 feet, is studded with sponges and corals and is home to a number of larger fish species including grouper, angelfish, jacks, and several pelagic fish species. The depth and strong currents at this location make the Thunderbolt a dive location for advanced divers only. Divers can explore the propellers, wheelhouse, and engine room of the Thunderbolt, which are all still intact.
