The world's scariest sports

Competitive free diving, meanwhile, is one of the world’s most controversial sports, due to the unnatural physical extremes under which divers put their bodies. Participants regularly plunge to depths of 400 or 500 feet, holding a single breath for as long as three to four minutes. Spectators at a free diving competition accompany the competitors in a boat to the dive site. Once there, two viewing options are available: Either snorkel on the surface and watch as the divers disappear into the murky depths (“the cheap seats”), or scuba dive 50 to 75 feet below, and witness the action from a fish-eye’s view (“front row” seats).

A more conventional — but no less precarious — water sport is white-water rafting, which under the best of conditions is still a true adventure. But for those who participate in the biennial World Rafting Championships, it can be either reputation-making or bone-breaking. Each championship is held at a location so dangerous, that a typical weekend white-water-rafter wouldn’t even think of wading into the river. In 2007, the competition took place in Korea’s daunting Naerinchon River. Previous years’ events were held in similarly brutal waterways in South America.

Chile, with its geographical and climatic extremes, is ideally suited to extreme sports of all kinds; and it is the self-anointed “birthplace of sand skiing.” This sport, which originated in the country’s Atacama Desert, takes place on sand dunes instead of ski slopes, and in 100-degree heat instead of below-zero chill.

Nicaragua, country of countless volcanoes, has recently one-upped Chile with a new, highly specialized activity known as “volcano surfing” or “ash boarding.” Participants spend an hour hiking to the summit of the 1200-foot Cerro Negro; then they soar down on a “sandboard” — a snowboard that has been adapted for the ash, sand and cinder surface of the volcano.

“The slope of the mountainside is 40 degrees — perfect for a good speed,” says Pierre Gedeon of Nicaragua Adventures, who was among the first to introduce volcano surfing to the public. Gedeon originally tried to navigate the rocky drops with skis, but switched to the adapted board because he found it easier for casual athletes to manage.

“The maximum speed is 25 miles an hour,” he says, “and we have even done it in the active crater. But we can’t seem to bring people — it’s too dangerous.”

For now. By 2009, it may be a whole different story — that is, if the new breed of thrill-seeking travelers has anything to say about it.

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