Annapurna is a massif in the Himalayas in north-central Nepal that includes one peak over 8,000 metres (26,000 ft), thirteen peaks over 7,000 metres (23,000 ft), and sixteen more over 6,000 metres (20,000 ft). The massif is 55 kilometres (34 mi) long, and is bounded by the Kali Gandaki Gorge on the west, the Marshyangdi River on the north and east, and by Pokhara Valley on the south. At the western end the massif encloses a high basin called the Annapurna Sanctuary. Annapurna I Main is the tenth highest mountain in the world at 8,091 metres (26,545 ft) above sea level, and in 1950 Maurice Herzog led a French expedition to its summit, making it the first of the eight-thousanders to be climbed.