Sansha Post Office is located in Beijing Road, Yongxing Island, Xisha District, Sansha City, Hainan Province (with the brand of "Sansha Post Office"). Formerly known as Southwest zhongsha islands Post Office (with the brand of "Southwest zhongsha islands Post Office"), it was established in 1953. After the establishment of Sansha Post Office, the service facilities and environment have been further improved, the service items have been broadened, and the island frontier postal service has been strengthened to serve the local party, government, army and people, thus supporting the economic and social development and national defense construction of Sansha City with practical actions.

Sansha City is a prefecture-level city under the jurisdiction of Hainan Province and the southernmost prefecture-level administrative region of China. It is also the city with the largest total area, the smallest land area and the least population in China. Located in the south-central South China Sea of China and the south of Hainan Province, it governs the islands and reefs of Xisha Islands, zhongsha islands and Nansha Islands and their sea areas, with a land area of more than 20 square kilometers and a land and sea area of about 2 million square kilometers.

Geographical environment where Sansha post office is located

Zhongsha islands is a marine island, which is a coral reef similar to Xisha Islands. They are developed in the central deep-sea basin and the top of Shanghai mountain on the northern slope. They are composed of 26 named shoals and 4 scattered shoals on Huangyan Island and Zhongsha Atoll, including General Shoal, Constitution Shoal, Shenhu Shoal and Zhongnan Shoal. Except for the reef edge of Huangyan Island Atoll, all shoal reefs are hidden in the sea, with depths ranging from tens of meters to hundreds of meters from the sea surface.

The westernmost part of zhongsha islands is Guanguantan, and its geological structure is similar to that of Xisha Islands. It belongs to one of the components of the continental margin graben system in the South China Sea, and its macro landform is coral reef landform of Zhongsha submarine plateau.

The above contents refer to Baidu Encyclopedia-Xisha District, Sansha City.