So it is wise to rely on their dive plans. A day of diving in the Caymans typically includes a deep first dive, followed by a short rest and then a shallow dive at the same spot, or at a suitably shallow site. The pinnacle is more prominent than the surrounding spur to which it is usually connected, although you will sometimes come accross large, isolated pinnacles like the one at Ghost Mountain. Spurs are long strips or fingers of rock and coral separated by deep sandy channels, known as canyons or grooves. The spurs are sometimes so close to one another that they meet above the grooves, and take on the appearance of a tunnel.
Tunnels are also termed crevices, ravines or swim-theorhs.
The wall or dropoff is actually at the end of the shelf, the point at which the realy deep water begins. Sometimes it takes the form of a very steep sand slope, while elsewhere it is a steep wall fissured by caves and canyons where protruding pinnacles are very much in evidence. In certain locations, the wall is oblitereated behind a veritable waterfall of sand, originating in the sand plain above. This spectacular river of sand is called a sand chute. Whatever their specific make-up, walls and dropoffs are what diving in the Cayman are all about.