The Changzhu Monastery on the east bank of the Yalong River in the district of Shannan. There is a legend behind the monastery. It is said that once upon a time, the site of the monastery was an extremely deep lake. In the lake there is a five-head dragon. After Srontsan Gampo got the control of Tibet, he wanted to drain the lake and build a castle there. So he invited two Masters to lure a big bird to attack the dragon. The two Masters, first of all, imitated the sound of the bird and lured the dragon out, then they imitated the sound of the dragon to lure the bird out. So the dragon and the bird started a fight. The bird at last chopped offtwo of the dragon’s heads with its wings. Seven days later, the lake disappeared. Some pearls were buried as the cornerstone for the monastery. That is how the monastery got its name.