The expedition was sponsored by National Geographic and apparel maker the North Face, with support from Montana State University.

WSJ: Mayo Clinic Researchers on Everest Study High Altitude's Effects on the Body

It was day two of our voyage aboard the National Geographic Endeavor, a 96-passenger expedition ship that sails 10-day itineraries around the 13 major, and many smaller, islands that span the Equator.

BBC: The Gal��pagos Islands, a land untouched

Previously, National Geographic Traveler included a 300-mile (483km) sea kayaking expedition along Scotland's west coast as the only UK entry in its list of 50 Tours of a Lifetime.

BBC: On the West Highland Way

Mountain climbers often set off on expeditions to summit unconquered peaks, but in this month's edition of National Geographic Radio Expeditions, NPR's Alex Chadwick tells the story of four mountaineers on a daring expedition across a vast, desolate landscape in northern Tibet for the goal of conservation.

NPR: Chang Tang's Endangered Antelope