The Florida Keys deserve mention because of their warm, clear waters and, more importantly, because they are home to the only living coral barrier reef in U.S. waters. The exotic array of underwater plants and marine animals creates one of the best diving experiences that divers, novice or expert, are likely to have without having to carry a passport. This is also one of the most well-protected reefs in the world. Yes, the ecosystem is fragile, but a variety of features, including mooring buoys that keep boats from having to drop anchor on the coral, make it possible to explore this place without having to worry about damaging it. The Keys area is also littered with a variety of shipwrecks. Many are located in relatively shallow and clear water, making them ideal for novices seeking an easy first wreck-diving experience.