Lukhang (Tib. klu khang, residence of Nagas), formally Zongdag Lukhang (Tib. rdzong bdag klu khang [?], residence of Nagas, lords of the castle and administered territory [?]) is the name of a secret temple of Lozang Gyatso, 5th Dalai Lama. Three walls of the temple are covered with murals of yogis engaged in their exercises.
The temple is situated on a small island on a lake behind the Potala palace in Lhasa.
References
Lukhang Wikipedia(Text) CC BY-SA