In the process of building the Diaoyucheng Fortress, all the stone materials for building the city were obtained from local sources. The stones are gathered to form a depression, and the water a pool. In addition to the big Tianchi, there are 13 small ponds in the Diaoyucheng Fortress.
    The quarry ruins was originally a small Tianchi, and the traces left by quarrying on the surrounding stone walls are still clearly visible. In order to expose visitors to the difficulty of building a Diaoyucheng Fortress and the hardships of ancient people, the small Tianchi was cleaned up in 2012, and sculpture experts were invited to create an array of life-size figure statues, which breathed life into the scene of stone quarrying in Diaoyucheng Fortress more than 700 years ago.