A wood and rope ladder proves to be an obstacle for students wielding twin tanks while attempting to climb to dry land at Mole Harbor off of Key West, Fla., during the Combat Diver Qualification Course, March 16, 2010. The CDQC is held at the Special Forces Underwater Operations School in Key West, part of the U.S. Army John F. Kennedy Special Warfare Center and School located at Fort Bragg, N.C.