Stretching 193km from Key Largo to Key West, this aggressive artificial reef program supplements the area’s shallow, fish-filled reefs and the wrecks of early 1700s Spanish galleons. Free dive logs highlight the main sites, such as the massive radar dishes of the 160m-long missile tracker USS Vandenberg, which is host to an underwater photo exhibit. North of Key Largo, near Miami, the Spirit of Miami — an entire Boeing 727 jetliner sunk in Biscayne Bay in 1993 — was rediscovered in multiple pieces in 2010. (Courtesy of The Florida Keys/Newman PR)