1. There are three different opinions about the origin of the Double Ninth Festival. One is from the fact that the number of nine yang in the Book of Changes is equal, the other is from the ancient activities of offering sacrifices to the heavenly harvest, and the third is from the ancient ceremony of offering sacrifices to Mars.

2. Legend 1: According to legend, the custom of climbing on the Double Ninth Festival began when Qin Shihuang ordered Zheng An, a warlock, to go to Lingnan to find the elixir of life. When Zheng An found Jiucalamus in Baiyun Mountain, he unfortunately fell off a cliff and was hoisted by a crane.

3. Legend 2: Climbing the mountain brings back the fire of thunder and lightning: The ancients thought that the mountains were shrouded in clouds and lived with dragons calling thunder and lightning. Moreover, lightning in the mountains can bring kindling, and you can make a fire to eat cooked food with foul smell.

4. Double Ninth Festival, New Year's Eve, Tomb-Sweeping Day and July 30th are called the four traditional ancestral festivals in China.