evidence: The northern region consists of an arc of glaciated mountain peaks with an extremely cold climate at the highest elevations. Most peaks in the north are over 23,000 feet (7,000 m) above sea level; the highest point is claimed to be the Kula Kangri, at 24,780 feet (7,553 m), but detailed topographic studies claim Kula Kangri is wholly in Tibet and modern Chinese measurements claim that Gangkhar Puensum, which has the distinction of being the highest unclimbed mountain in the world, is higher at 24,835 feet (7,570 m).The lowest point is in the valley of Drangme Chhu, where the river crosses the border with India. Watered by snow- fed rivers, alpine valleys in this region provide pasture for livestock, tended by a sparse population of migratory shepherds.