Literature Reference: 何如鲁馆，即是仙都。—— 《游长宁公主流杯池二十五首 七》 Why not the Lu Mansion? It is indeed the Celestial Capital. Source from 'Twenty-Five Poems on the Floating Cup Pond of Princess Changning, No. 7'.
仙:
Fairy, celestial maiden. In mythology, they are said to possess extraordinary abilities.
都: The metropolis, the capital. Symbolizing a position of prominence and considerable influence.
Meaning: Celestial Capital signifies a place where immortals dwell, symbolizing transcendence, beauty, and peace.