Introduction to Liuzuo: Liuzuo Pond is located at the southern end of the Ming Dynasty Bao Shipyard site, about 430 meters long and 50 meters wide. With the approval of the State Administration of Cultural Heritage, from 2003 to 2004, the Nanjing Museum organized archaeologists to conduct a rescue cleanup and excavation of the Liuzuotang in the Bao Shipyard site. The clearance and excavation area was nearly 20,000 square meters, of which 16,000 square meters were excavated at the bottom of the dock. 34 "dock" relics of various types were cleared out, and unearthed wood, iron, stone, brick, brown, pottery, porcelain, etc. There are more than 1,500 pieces of various cultural relics of different textures. Very important archaeological gains have been made.