Located on a hill facing Gangtok, Rumtek is the largest monastery in Sikkim. The Tibetan-style monastery the seat of the Kargyupa sect of Buddhism and a near-replica of the Kagyu headquarters in Tibet. It comprises a temple, a school, an aviary, several stupas, a retreat for monks to meditate and other buildings. Originally built in the 16th century, the monastery was damaged by an earthquake and was rebuilt by the 16th Karmapa.

The main temple is a four-storey building topped by a golden sculpture, and decorated by Tibetan-style murals. The shrine hall is decorated with silk banner and thangkas, and houses numerous religious texts as well as a ten-feet-high statue of Sakyamuni Buddha. The monastery also celebrates various festivals throughout the year. On Gutor, held at the end of the Tibetan year (February or March), the monks perform chaam or ritual dances in the main courtyard for the public.