Nanda Devi is the second highest mountain in India and the highest entirely within the country (Kangchenjunga being on the border of India and Nepal); owing to this geography it was the highest known mountain in the world until computations on Dhaulagiri by western surveyors in 1808. It was also the highest mountain in India before Sikkim joined the Indian Union. It is part of the Garhwal Himalayas, and is located in the state of Uttarakhand, between the Rishiganga valley on the west and the Goriganga valley on the east. Its name means Bliss-Giving Goddess.
The ascent of Nanda Devi necessitated fifty years of arduous exploration in search of a passage into the Sanctuary. The outlet is the Rishi Gorge, a deep, narrow canyon which is very difficult to traverse safely, and is the biggest hindrance to entering the Sanctuary; any other route involves difficult passes, the lowest of which is 5,180 m (16,990 ft). Hugh Ruttledge attempted to reach the peak three times in the 1930s and failed each time. In a letter to The Times he wrote that 'Nanda Devi imposes on her votaries an admission test as yet beyond their skill and endurance', adding that gaining entry to the Nanda Devi Sanctuary alone was more difficult than reaching the North Pole.
Nanda Devi is a two-peaked massif, forming a 2 kilometres (1.2 mi) long high ridge, oriented east-west. The west summit is higher, and the eastern summit is called Nanda Devi East. Together the peaks are referred to as the twin peaks of the goddess Nanda. The main summit stands guarded by a barrier ring comprising some of the highest mountains in the Indian Himalayas (one of which is Nanda Devi East), twelve of which exceed 6,400 m (21,000 ft) in height, further elevating its sacred status as the daughter of the Himalaya in Indian myth and folklore. The interior of this almost insurmountable ring is known as the Nanda Devi Sanctuary, and is protected as the Nanda Devi National Park. Nanda Devi East lies on the eastern edge of the ring (and of the Park), at the border of Chamoli, Pithoragarh and Bageshwar districts.
In addition to being the 23rd highest independent peak in the world, Nanda Devi is also notable for its large, steep rise above local terrain. It rises over 3,300 metres (10,800 ft) above its immediate southwestern base on the Dakkhni Nanda Devi Glacier in about 4.2 kilometres (2.6 mi), and its rise above the glaciers to the north is similar. This makes it among the steepest peaks in the world at this scale, closely comparable, for example, to the local profile of K2. Nanda Devi is also impressive when considering terrain that is a bit further away, as it is surrounded by relatively deep valleys. For example, it rises over 6,500 metres (21,300 ft) above the valley of the Ghoriganga in only 50 km (30 mi).
On the northern side of the massif lies the Uttari Nanda Devi Glacier, flowing into the Uttari Rishi Glacier. To the southwest, one finds the Dakkhni Nanda Devi Glacier, flowing into the Dakkhni Rishi Glacier. All of these glaciers are located within the Sanctuary, and drain west into the Rishiganga. To the east lies the Pachu Glacier, and to the southeast lie the Nandaghunti and Lawan Glaciers, feeding the Lawan Gad; all of these drain into the Milam Valley. To the south is the Pindari Glacier, draining into the Pindar River. Just to the south of Nanda Devi East, dividing the Lawan Gad drainage from the Dakkhni Nanda Devi Glacier, is Longstaff Col, 5,910 m (19,390 ft), one of the high passes that guard access to the Nanda Devi Sanctuary. For a list of notable peaks of the Sanctuary and its environs, see Nanda Devi National Park.