sandu island has a long history, rich inside information and a well-known reputation. It was developed as early as the Tang Dynasty. In 1684, it set up a general tax port, officially opened it as a foreign trade port in 1898, established the Fu Customs in 1899, and established the telegraph office of the Qing Empire in 195. Thirteen countries, including the United States, Britain, Japan and France, set up offices, start-up companies, foreign firms, shipping companies, insurance companies, money houses and tea shops here, and the three largest banks, the Central Bank, the Bank of Communications and the Agricultural Bank, set up branches here. The centuries-old customs on the island, the vicissitudes of nunnery and Gothic churches, monasteries and other European architectural sites are all telling the prosperous history of sandu island. The world intangible cultural heritage-watertight compartment shipbuilding technology, witnessed the culture of farming, animal husbandry and fishing. Zhu Yuanzhang, Zhu Xi, Lu You, Zheng He, Hu Yaobang, Li Xiannian, Guo Moruo, Qian Weichang and many other literati, heroes, experts and scholars traveled and inspected here, leaving a famous quatrain of praise.

The centuries-old customs on the island, the vicissitudes of European architectural sites such as nunnery and Gothic church can all witness the prosperous history of Sandu. The best preserved Spanish church in Fujian Province is located in Beishan Yu. Just 1 meters away from the back of the Catholic Church, is the convent of sandu island. At the end of the Qing Dynasty, there were more than ten nunneries in sandu island, and only one yard was left in the fire. The most attractive thing in sandu island today is the floating city on the sea. The floating city, which consists of numerous fish rafts, is the only existing large yellow croaker breeding base in the world. There are many hotels in the floating city. It's really "fresh" to eat seafood here, so you can just fish it in the sea and cook it.