Into the fridge. (Antarctic region) (Cover Story)

At the bottom of the world, getting the photo often means a brush with danger

Where the antarctic region begins is fuzzy at best. Biologists often define it well north of the Antarctic Circle where cold waters from the south converge with more temperate seas. The Antarctic Treaty places it more precisely at 60 degrees latitude. I see the southernmost continent and the subantarctic islands to its north as part of a greater whole. These lands represent some of the last, vast unbroken wild environments on Earth.

Of course, the Antarctic is far more than just a symbol. As an adventurer, climber, photographer and conservationist, I have been there three times, once on a grant from the U.S. National Science Foundation. Along the way, sometimes in dangerous places, I've encountered incomparable natural wonders.

One of these is the active volcano, Mount Erebus, 3,794 meters (12,447 ft.) above the Ross Sea, where freezing vapors from hot fumaroles have created towers of steaming ice (right). I rappelled 25 meters (85 ft.) into one of them. At the bottom were dark catacombs floored with pumice and roofed with giant ice crystals.

The descent into this frozen inferno was but one step in my exploration of a wondrous region I've documented with the photographs on these pages.

Warding off Antarctica's legendary cold, my traveling companion Tory Kooyman peers from behind a face mask, his nose swathed in bulbous insulation (right). We were headed for a colony of emperor penguins at Cape Crozier, where in 1911 three members of Robert Falcon Scott's expedition …