K2, the world's second highest mountain, richly deserves the place it has earned in the public's imagination as an equal to Everest in the mountain pantheon. The question of what is the hardest mountain in the world to climb will never be objectively determined, but K2 offers as compelling a case as any peak for the honor: extreme altitude, massive scale, steep slopes on all sides, unstable weather, killer avalanches, remoteness from roadheads, and a location in a politically unstable region near a war zone.
K2 lords over the Karakoram Range on the border of Pakistan and China, and is not located in the Himalaya (although calling the Karakoram part of a vague "Greater Himalaya" region would not be totally inaccurate). It is a massive pyramid, without the major sub-peaks, shoulders, or buttressing ridges common on the Himalayan peaks like Everest. To climb K2, you must really climb it, from the base, and there are no shortcuts.
The peak's name is an old survey designation from the 1800s, when the peaks in the Karakoram range were numbered K1, K2, K3, etc. by early surveyors. Appropriate local names were found for other peaks, but K2's isolation left it without one. Altenate names have been put forward over the years, both pseudo-local (Dapsang, Chogori) and European (Mount Godwin-Austen), but by now the simple, stark, two-character code is not only universally accepted, but is even seen by some as somehow fitting for this simple, stark, and majestic peak.