The mountain was first surveyed by a European survey team in 1856. Team member Thomas Montgomerie designated the mountain K2 for being the second peak of the Karakoram range. The other peaks were originally named K1, K3, K4, and K5, but were eventually renamed Masherbrum, Gasherbrum IV, Gasherbrum II, and Gasherbrum I, respectively. In 1892, Martin Conway led a British expedition that reached Concordia on the Baltoro Glacier.