According to legend, there was a father and son named Yan, father named Yan and son named Yan. The two men fled from Shandong to the south and began to work for a rich family. The rich man saw that Feng Yan was old and sick, and there was no oil and water to squeeze, so he drove his father and son out of the house. Yanwu and his son have to beg for a living, often without food and often dizzy from hunger. Especially the elderly father, has been seriously ill. Fortunately, Yanwu is a dutiful son and serves his father well.
On one occasion, Yan Wu found a small cave on the way to beg. The area of the cave is small, but it is warm in winter and cool in summer. Yanwu was overjoyed. He tidied up the cave and the father and son settled down in it. In summer, there are more and more mosquitoes in the caves. How to make a seriously ill father sleep well and not be disturbed by mosquitoes? Smart and filial Yan Wu has her own way. Every evening, Yan Wu always carried his father outside the cave to enjoy the cool, and then he went back to the cave and lay down naked. An hour later, the mosquito "retreated" contentedly. Yan Wu got up and went back to the cave to sleep with his old father on his back.
Yan Wu's filial piety always touched a nest of crows living in the mouth of the cave. These crows eat mosquitoes when they see them, and then the mosquitoes in the hole are gone. When I come back for dinner, I will also leave some food for the crow. Father and son and crow have become good neighbors.
At first light, the crow was suddenly awakened by a cry of pain. It turns out that Yanwu's father has passed away. Yan Wu cried her eyes out at the mouth of the cave holding her father's body ... When a person dies, she must be buried, because there is no tool, Yan Wu can only dig her father by hand. Crows were moved by his filial piety, and thousands of crows flew to Yanwu and his son, each with a white mourning circle around his neck. After several turns, the crow flew to the northwest again. They picked up the dirt from the yellow land 1 km away and piled it next to Yan Feng ... These crows were busy flying back and forth. Soon, the crow's beak was injured and the mud was stained with a little crow's blood. At night, the crow built a high grave.
It is said that after the death of the dutiful son Yan Wu, the crow was buried next to his father's grave. People built an ancestral temple here, called the filial piety temple. In memory of the crows who were injured while building graves, people called this area a black wound.