To the east of Penglai(蓬萊) , there is a country called Yuyi, where golden mists frequently appear. The immortals say that this mountain often floats within the mist, sometimes rising high, sometimes hanging low.
Many buildings stand on the mountain, their windows usually facing towards the bright direction when the mist disperses, and all facing north when the mist vanishes.
~鐘毓龍 《上古秘史》, in the Qing Dynasty
I think the earliest record of that is in 《拾遺記》, will talk about that in the next thread.