Vertical Limit: K2, The Savage Mountain

Turning north from Baltoro, climbers trek the Godwin-Austen Glacier toward K2. Named for an early explorer of the region, Henry Haversham Godwin-Austen, the glacier leads to K2's base camp (at 5,135 meters altitude). Broad Peak, just east of the Godwin-Austen glacier, overlooks the route to K2.

Although the base of the mountain (from the Godwin-Austen glacier) is a sight to behold, (as it is from the Gasherbrum Glacier), getting to that point is comparatively hazard-free. Ascending to the summit - only attempted by the most fit and experienced climbers - is marked by both obvious and hidden dangers.

Constant snow cover completely masks openings to ice caves and crevasses. Even the most seasoned climbers can fall into a crevasse or cave without warning. (The links take you to a snow picture - from the stunning perspective of a scanning electron microscope.)

Vittorio Sella, the renowned Italian mountain photographer, took the first pictures of K2 and its pitfalls. It was 1909. Sella had previously ordered a special camera weighing 40 pounds to record what he found. Such scenes as 1888's Crevasse on the Glacier Blanc, although not taken on K2 itself, demonstrate the perils of a crevasse.

Ice caves can be even worse because of their size. Caverns, they can be unmanageable for climbers to exit without rescue. And rescue, on K2, may not always be possible.