Yumbu Lhakhang is the first palace of Tibet

Yumbu Lhakhang, the first palace of Tibet, is located on the Zhaxi Ceri Mountain, 5 kilometers from Nedong County in Lhoka Prefecture.
A legend counts Yumbu Lhakhang Palace as the first palace in Tibet. According to a legend of followers of the Bon Religion, Yumbu Lhakhang Palace was erected in the second century BC for the first Tibetan king Nitri Tsampo, who was believed to descende from the sky.

As the ancient palace of the Tibetan kings prominenting on a rocky hill, it is a narrow rectangular building with a slender white tower topped by a gilded rgya-phibs canopy. According to Tibetan legend, during the reign of the 28th king Lha Thothori Nyantsen in the 5th century, the first Buddhist Sutra to enter Tibet fell from the sky onto the roof of Yumbu Lhakhang together with a small golden stupa and a jewel.By tradition it was founded by the mythical king Nya-khri Btsan-po and it is associated, rather more possibly, with king Tho-tho-ri who may be placed tentatively in the middle of the fifth century. The story gives sanctity to the building which, which is approached by a narrow path up a steep hill and entered through a low door beyond which a steep ladder leads to the first floor.