The Blue Hole at Lighthouse Reef Atoll (an atoll is a sunken island - but on our boat it has come to mean...well, it has other meanings) was created when an underwater cavern sunk into itself. It makes a near perfect circle about 1000 feet across and 400 feet deep. It is a popular dive destination here in Belize with boats shuttling divers regularly from the mainland and the barrier islands. When we visited we were unbelievably lucky to have it completely to ourselves. It was magnificently eery to snorkel the reef that lines the perimeter of the hole. The reef itself is in shallow water but the depth plunges dramatically into darkness just a few feet away. The underwater pictures below are from our snorkel.