Which mountain is the hardest to climb?

K2, on the border of Pakistan and China, stands at 8,611 metres, second only to Everest, but it is considered far more difficult and dangerous to climb. Its steep, exposed slopes, unpredictable and severe weather, and technical routes make it deadly, and it has a much higher fatality rate than Everest. It was long known as the Savage Mountain and has never been climbed by a large number of people compared with Everest. Annapurna, another Himalayan giant, has one of the highest death rates of all. These peaks push mountaineers to the limits of endurance and skill.