The Trango Towers are a group of dramatic granite spires located on the north side of the Baltoro Glacier, in Baltistan, a district of the Northern Areas of Pakistan. They are part of the Baltoro Muztagh, a subrange of the Karakoram range. The Towers offer some of the largest cliffs and most challenging rock climbing in the world. The highest point in the group is the summit of Great Trango Tower, 6,286 m (20,608 ft). (Note: all elevations in this article are subject to significant uncertainty: it is not clear if they have ever been determined precisely, and sources vary.) The east face of the Great Trango Tower features the world's greatest nearly vertical drop.