Introduction to Wuzuo: Wuzuo Pond is about 430 meters long and 50 meters wide. Many shipbuilding relics have been discovered, including large cultural relics such as wood, ironware, tung oil, hemp, lime, masts and sampans. At the same time, A large stone mortar, used for beating hemp silk, and an iron anchor 1.86 meters long. The anchor also has four claws, each claw is 0.92 meters long. The claws are slightly straight and have slightly protruding links. Existing in Nanjing Museum.