The four ancient towns in Chongming Island include Qiaozhen, Miaozhen, Baozhen and Xianghua Town. These ancient towns have a long history and rich culture and characteristics. Qiaozhen was formed due to irrigation and water conservancy, and residents of Miaozhen made a living by shipping. Baozhen built castles to defend against Japanese pirates in the Ming Dynasty, and Xianghua Town was named after the imperial examination. The unique history and characteristics of these ancient towns are isomorphic to form the unique cultural landscape of Chongming Island.