Cliff diving is an ancient athletic activity with the modern attractions of all of the extreme sports where the effect of gravity plays the most significant role. As the name suggests, cliff diving involves the execution of various types of dives from natural features such as cliffs or other high, rocky precipices that over look a large body of water. Cliff diving is closely allied to high diving, an activity that can be pursued from any high place adjacent to or spanning water, such as a bridge or trestle.
The English explorers who first visited Hawaii in the early 1770s noted the chief of the indigenous peoples diving from the cliffs into the ocean, deliberately making a feet first entry into the water so as to generate little or no splash. Cliff diving was also a part of the Mayan culture of southern Mexico; La Quebrada is the most famous of these diving locales and it remains a tourist attraction today.
Cliff diving is now organized on an international basis through the World High Diving Federation (WHDF), with its headquarters in Switzerland. The WHDF sanctions an annual world championship and it has established a qualification and competition judging system that is akin to the manner in which dives are judged in the more conventional Olympic settings.
A basic cliff diving technique is a dive that ends with an entry head first into the water. Cliff divers are taught to extend their arms with the palms of their hands held tightly together to protect the face from the impact of the water. On contact with the water, the hands enter the water first, and as the diver is moving at a high speed, the hands create a stream of bubbles in which the diver is surrounded as the diver's body makes contact with the surface. At a height of 33 ft (10 m), the diver shall strike the water at a speed of over 30 mph (50km/h). With a dive from 100 ft (30 m), the diver strikes the water at a speed of over 53 mph (87km/h). These speeds contribute to the large forces generated when the diver enters the water. For these reasons the diver's entry must be as precise and as efficient as possible.