The port city of H?i An and its bridge within the 18th century. Watercolour engraving by Jacques Chereau (1688-1776), circa 1750. H?i An's value waned sharply at the conclusion of the 18th century because of the collapse of Nguy?n rule, which resulted in the Tây S?n Rebellion - which was against international trade.Administration map of Hoian City