《徐霞客游记·游恒山日记》
坊右往东顺台阶上去，山崖半腰有寝宫，寝宫北是飞石窟，相传真定府的恒山是从这里飞去的。
坊右东向拾级上，崖半为寝宫，宫北为飞石窟，相传真定府恒山从此飞去。
Heading east from the pailou to the right along the steps, there is a bedchamber halfway up the mountain. North of the bedchamber are the Feishi Grottoes. Legend has it that Hengshan Mountain from Zhendi prefecture flew here.