1279, Yuan Shizu conquered and destroyed China in the Southern Song Dynasty. According to the records in the Atlas of Chinese History, Handi, Monan, Mobei, Northeast (including Outer Manchuria and Sakhalin Island), Dongjiang (according to Tarim Basin, it reached Qingji in the west in the early Yuan Dynasty), Qinghai-Tibet Plateau, Penghu Islands, Jeju Island and South China Sea Islands were all within the jurisdiction of the Yuan Dynasty.
After the Southern Song Dynasty, although there were many conflicts with Japan, Myanmar, Annan, Java and other countries, the territory generally tended to be stable. 13 10 During the Yuan Wuzong period, Wokuotai khanate was divided into Yuan Dynasty and Chahetai khanate. The Yuan Dynasty acquired the territory of Wokuotai khanate Moxi, with a land area of13.72 million square kilometers (the northern Xinjiang is bounded by 55 north latitude). If the northern Xinjiang is extended to the Arctic Ocean, it will have 22.67 million square kilometers.
Modern territory of China:
China's territory includes Chinese mainland and its coastal islands, Taiwan Province Island, Hainan Island, Diaoyu Island, chiwei yu and its affiliated islands, dongsha islands, Xisha Islands, zhongsha islands and Nansha Islands. The total land area is about 9.6 million square kilometers, and the total sea area is about 4.73 million square kilometers. The length of China's land border is about 22,000 kilometers, and the length of the mainland coastline is about1.8000 kilometers.
The land area of China ranks third in the world, only next to Russian and Canadian. In addition to the mainland, coastal islands are also an important part of China's territory. There are more than 7,600 large and small islands in the sea area, of which Taiwan Province Island is the largest, with an area of 35,759 square kilometers. China borders 14 countries and is adjacent to the sea of eight countries. Hainan Island is the second largest island in China with an area of more than 33,000 square kilometers. Other islands are smaller, and most of them are distributed in the mainland coast and the South China Sea south of Hangzhou Bay.
The territorial sea refers to all waters and subsoil under the jurisdiction of national sovereignty and is an important part of national territory. Territorial waters include internal waters and territorial waters. Internal water refers to the waters within the national territory and the waters on the land side of the territorial sea baseline, including rivers and their estuaries, lakes, ports, harbors and inland seas.