A trip that challenges the limits of physical exertion and mental grit is not
considered a vacation at all by most people. But for the rare breed of
explorer who believes in testing one's mettle at every opportunity, there is
a world of wonderfully adventurous travel out there. Safaris and rain forest
excursions provide a glimpse of wildlife left untouched for centuries. Arctic
and Antarctic expeditions bring hardy voyagers to the world's most extreme
environments. And mountain climbing, cycling, and other exhilarating outdoor
activities add adventure to more traditional destinations.