This Manilakhang is located above the Beechu Village of Lachung, North Sikkim. It is said to have been founded in 1788 A.D, by the devotees on the site once blessed by Ngadag Rinchen Gon (Grant son of Ngadag Sempa Chenpo) during his visit to this area. This is the first Buddhist monastery in this area. The Altar contains Cho-Long-Trul-sum Statues.

A Rinpoche named Thung Rinpoche from Kham, Tibet spent some years taking care of this Gonpa. This Rinpoche was highly accomplished master in Yogic power and his fame of spiritual power reached to the people of Lachung. He was invited to Lachung by the people at a time when the livestocks of the Village of Lachung was under frequent attacks by wild dogs.These attackst destroyed a large population of the domestic animals therefore, onn the request of the villagers, Rinpoche had performed a puja after which the menace of the wild dogs completely vanished from Lachung till this day. Later Rinpoche shifted to Ringhim Gonpa where he expired. Thung Rinpoche got his name from the sacred conch shell he carries with him. However, his relics were collected by Lachung devotees and enshrined in a stupa near the Manilhakhang. The Gonpa has a large Thanka of Guru Rinpoche painted by Sikkim’s most famous artist Bermiok Lharipa. Manilhakhang special ceremony is ‘Thung Jalkha’(Darshan) the sacred conch shell which was said to have been discovered as a ‘gTer’ from a lake called Manirangding at Tsari in Tibet by a famous gTer-bTon (Treasure Revealer) named Di-kung Jig-ten Kun-chok. The conch shell, it is said to have flown to a hill at Tsari where it spoke. It wanted to be at a place called Thung-kar Gon. Later, Rinpoche had obtained it from Thung-kar Gon. This conch Shell is supposed to have miraculous powers and has been seen to produce Ringsel and Holy water. It is now kept in this Lhakhang and is shown to all the devotees on the 15th day of (Tshe Che-nga) of the first month of the Tibetan year. This monastery follows Changter lineage of Nyingmapa Sect.