According to the query of Baidu Education, the topic: The total length of China's coastline is (). A: The total length of China's coastline is over 32,000 kilometers. Among them, the mainland coastline starts from the mouth of Yalu River in the north and reaches the mouth of Beilun River in the south, with a total length of 1.8 million kilometers. The coastline of the island is as long as1more than 4000 kilometers.

Coastline is the dividing line between ocean and land, and it is more precisely defined as the connecting line between the extreme positions of ocean and land. Go with the flow. Due to the influence of tidal action and storm surge, the sea rises and falls, the sea surface rises and falls, and the boundary between ocean and land is constantly changing. Therefore, the actual coastline should be a collection of countless land-sea dividing lines between high and low tides, which is a strip in space, not a line with a fixed geographical position.