Yaochi on the top of Kunlun Mountain is the legendary residence of the Queen Mother of the West.
The Biography of Mu Tianzi, Volume III: "Ugly, the Tianzi invited the Queen Mother of the West to be above the Yaochi."
Penglai three mountains refer to the three fairy mountains in ancient China mythology-Penglai, abbot, Yingzhou
Nantianmen, Tiangong, Gouchen Shanggong, Taiwei Yuqing Palace and Lingxiao Baodian.