Bottleneck (K2) Bottleneck (K2) The Bottleneck is a location along the South-East Spur, known also as Abruzzi Spur— the most used route to the summit of K2, the second-highest mountain in the world, in the Karakoram, on the border of Pakistan and China. The Bottleneck is a narrow couloir, which is overhung by seracs from the ice field east of the summit. The couloir is located only 400m below the summit, and climbers have to traverse about 100m exposed to the seracs to pass it. Due to the height (8200m) and the steepness (50-60 degrees) this stretch is the most dangerous part
Baltistan of mountains in the world and the biggest glaciers outside the polar regions. The Himalayas advance into this region from India, Tibet and Nepal, and north of them are the Karakoram range. Both ranges run northwest, separated by the Indus River. Along the Indus and its tributaries are many valleys. Glaciers include Baltoro Glacier, Biafo Glacier, Siachen Glacier, Trango Glacier and Godwin-Austen Glacier. Baltistan is home to more than 20 peaks of over , including K2 (the second-highest mountain on earth. Other well-known peaks include Masherbrum (also known as K1), Broad Peak, Hidden Peak, Gasherbrum II, Gasherbrum IV and Chogolisa