The land in northwestern Tainan City was made up of an inland sea (lagoon) surrounded by several small islands; it was called Daofeng Inland Sea or Taijiang Inland Sea. At the time, ports lined the coast, making it the most important distribution center of resources in southern Taiwan. After the 18th century, Daofeng Inland Sea disappeared when it was silted up, and it was replaced by salt fields, fish farms and farmlands. The Stele Prohibiting Occupancy of the Water Channel at Bitou Harbor explains how the silted up land caused various power struggles, leading to serious social clashes. Since the natural environment at Taijiang Inland Sea is unfit for agriculture, most residents built fish farms at the lagoon, wetlands and estuaries. The Qing Dynasty continued the taxation system developed by the Dutch to manage inland sea economic activities, such as fish farms, fishing nets and fishing boats. After the 19th century, the tax income was allocated to the Taiwandao Government for use as the public affairs budget. This exhibit thus shows the changing official stance on the management of inland sea fisheries.