South of Miami and east of Homestead off Key Biscayne, the snorkeling at Biscayne National Park is offshore at a living coral reef. There are four primary snorkeling dive sites in Biscayne National Park: Ball Buoy Reef, Mandalay wreck, Sandwich Cove, and Bache Shoal. The Ball Buoy Reef is a relatively shallow reef with sea fans and elkhorn coral in 20 foot deep water, which is best snorkeled in calm seas. The coral and sea fan encrusted Manadalay wreck sits in 15 feet of water and is a good snorkeling dive if the water is shallow (part of the Shipwreck Trail). The Sandwich Cove snorkeling dive sites is good in calm or rough seas since it is protected. It offers diverse marine life. The Bache Shoal is a popular shallow coral reef in about 10 feet of water that is good for families. Bache Shoals is about 1 mile east of the Sand Cut channel. It has three mooring buoys above the brain corals which are good habitat for the diverse reef fish.
To reach the Biscayne National Park snorkeling from the Florida Turnpike, use Exit #2 for NE 8th Street. Head east on NE 8th Street and turn right heading south on SW 152nd Avenue. Turn left heading east on SW 328 Street (aka North Canal Street) for 9 miles to the Visitor Center. To reach the snorkeling in southeast Florida by air, there are several options. The most popular option is to fly into Miami International Airport (MIA), which is served by all major US and international airlines. Also nearby, a potentially lower cost option is to fly into Ft Lauderdale airport (FLL). From either of these airports, you can rent a car to drive to the dive site, but watch out for automated cash-less toll highways along the way.
While the park service normally has a concessionaire to provide a snorkeling charter to the dive sites, there was no active concessionaire as of September 2013.
Overall, Biscayne National Park is the 2nd most popular snorkel dive spot of all 24 snorkeling dives in Florida Southeast.