On the lower hillock, south east of Pemayangtse monastery, lies the ruin of the old Rabdentse palace. Rabdentse was the second capital of Sikkim established by the second Chogyal in the latter half of the 17th century. It was the capital of the erstwhile kingdom till 1814 A.D. The old palace and monastery complex are in ruins, and now Archaeological Survey of India is maintaining and undertaking the restoration works. The place is surrounded by dense forest with a water pond.

The scenic view from the top of the ruins scanning across deep valley to the mystic heights of Kanchendzonga ranges is something to be cherished and etched in memory. Here one can visualize the remains of a once flourishing colony around the palace which was constructed after the consecration of Chogyal Phuntshog Namgyal in the 1641 AD. On walking through the chestnut trees with the mosses dripping down, one can come across a stone throne with three standing stones known as Namphogang from where the judge used to give his final judgment in those days. One can also see Taphap Chorten, from where the visitors had to take off their hats to enter the palace. After crossing the fourth and the final courtyard wall we can see the palace ruins in the centre. It is situated in a most commanding place from where we can clearly see the entire southwestern region of Sikkim. Adjacent to the place is 'Dab Lhagang' Where the royal family used to offer incense to the deities.