Sanmen Bay

Sanmen Bay indents the Zhejiang coast between Ningbo and Taizhou, where islands and tidal channels separate the mainland from the East China Sea. Fishing and coastal transport connected communities around the bay and with neighboring districts. Its shores also supported salt production, an important source of revenue in the region.

The Changting salt works included production areas along the shore, while Dudu was another important salt-producing district to the south. In 1109 the Changting works moved its administrative seat from Gangtou to Changting. During the Ming and Qing periods, fishing, agriculture and sea traffic continued alongside salt making, within a coastal landscape subject to official regulation and concern for defense.