Nanda Devi (7816 m, 25,636 ft) is the second highest mountain in India, and the highest located entirely within the country. (Kangchenjunga, which is higher, is on the border of India and Nepal.) It is the 23rd-highest peak in the world. It was considered the highest mountain in the world before computations in 1808 proved Dhaulagiri to be higher. It was also the highest mountain in India before 1971 when Sikkim, the state in which Kangchenjunga is located, joined the Republic of India. 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. The peak, whose name means "Bliss-Giving Goddess",[4] is regarded as the patron-goddess of the Uttarakhand Himalaya. In acknowledgment of its religious significance and for the protection of its fragile ecosystem, the peak as well as the circle of high mountains surrounding itthe Nanda Devi sanctuarywere closed to both locals and climbers in 1983. The surrounding Nanda Devi National Park was declared a UNESCO World Heritage Site in 1988.A barrier ring guards the main summit, within which can be found some of the highest mountains in the Indian Himalayas, and Nanda Devi East is one of them. Twelve peaks surpass 6,400 meters in height. The heart of the insurmountable ring is the Nanda Devi Sanctuary which 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 Chamois, Pithoragarh and Bageshwar districts. The Nanda Devi West Peak towers at 7,817 meters and is the second highest in the country. Climbing expeditions are best taken up in the months of May, June, September and October.Nanda Devi Bio Reserve is the most spectacular wilderness areas in the Himalayas