Key Monastery is the biggest centre of Buddhist learning in Spiti Valley, Key Monastery is over 1000-year-old. It is the oldest training centre for Lamas. It is located at a height of 13,668 feet above mean sea level in Lahaul Spiti district of Himachal Pradesh in north India. Founded by Dromton, a famous disciple of teacher Atisha in the 11th century, the monastery used to house about 350 lamas at one time. The number of inmates at the monastery has come down. The monastery is famous for its architecture called Pasada style. Pasada style is characterised by two or more stories and often plays the role of a fort-monastery. The monastery is spread over three floors – underground, ground and first floor. Underground is mainly utilized for storage; ground floor is used as assembly hall, called Du-Khang. The ground floor also has small rooms for monks. The rooms with murals called Tangyur is a must see. The monastery is known for its ancient murals, rare thangkas and ancient weapons. The images of Gautam Buddha in dhyana (meditation) position are a must see. The monastery also has a sizeable collection of musical instruments like trumpets, cymbals and drums. Key Monastery was destroyed by invaders and rebuilt several times. In 1840 it caught fire and in 1975, it suffered extensive damage due to an earthquake. Having been rebuilt several times, temples and other buildings appear to have been stacked haphazardly. The monastery appears like a fortress.