Ladakh covers about 45,000 square miles (117,000 square km) and contains the Ladakh Range, which is a southeastern extension of the Karakoram Range, and the upper Indus River valley. Ladakh is one of the highest regions of the world. Its natural features consist mainly of high plains and deep valleys. The high plain predominates in the east, diminishing gradually toward the west. In southeastern Ladakh lies Rupshu, an area of large, brackish lakes with a uniform elevation of about 13,500 feet (4,100 metres). To the northwest of Rupshu lies the Zaskar Range, an inacce