Introduction to Tiantianmen: According to legend, Liu Xiu was chased by Wang Mang's army to Wangyou Valley in Yanzi Mountain. He encountered four stone mountains and was blocked from moving forward. When Liu Xiu was desperate, he cried out: "Who can save me!" Three stone mountains cracked in turn to form a stone gate, and Liu Xiu fled. When they arrived at the fourth stone mountain, Liu Xiu shouted, but the stone mountain remained motionless. Liu Xiu sighed: "Heaven is going to destroy me!" At this time, he saw a group of swallows passing over his head, and a plank road opened on the cliff. Liu Xiu led the remaining troops We followed the plank road to the top of the mountain in the direction in which the swallows flew. At this time, we saw that the swallows were nowhere to be seen. Because the four stone gates had contributed to the rescue, Liu Xiu gave them names: Tiantianmen (Happiness Gate), Ertianmen (Wealth Gate), Santianmen (Fumen), and Tiantianmen (Transfer Gate).