11. Gasherbrum I or Hidden Peak (Karakoram Range, Pakistan & China)
Height: 8080 meters (26,059 feet)
First Ascent: 1958
Image: Flickr User The Real Kvass
Height does not necessarily correlate with difficulty, although Everest does provide a huge challenge due to the amount of time a climber is required to spend in the Death Zone. That said, Annapurna I, the 10th highest mountain in the world, is often said to be the most difficult to climb and has a very low success rate, alongside an extremely high fatality rate, which was once upward of 40% but has now fallen to around 32%. Annapurna’s difficulty comes from its glacial ‘architecture’, which includes huge ice cliffs, sheer sides and massive seracs that are often disorientating. K2, Kangchenjunga and Nanga Parbat (often referred to as ‘Killer Mountain’) are also notoriously difficult to climb, with heavy risk of avalanche and rock fall.
12. Broad Peak or K3 (Karakoram Range, Pakistan & China)
Height: 8051 meters (26,414 feet)
First Ascent: 1957
Image: mountainsoftravelphotos.com