Beijing is the capital of the People's Republic of China and one of the most populous cities in the world. The metropolis is the political center, cultural center, international communication center, and scientific and technological innovation center of the country. It is the world's first dual Olympic city, and hosts 7 UNESCO World Heritage Sites.
Covering an area of 16410.54 square kilometers, Beijing lies on the north end of the North China Plain that is surrounded by mountains to its west, north and northeast. To its southeast is a plain that slopes gradually to Bohai Sea. Beijing has a temperate, semi-humid continental climate, characterized by short springs and autumns, hot and rainy summers, along with cold and dry winters.
For thousands of years, water has been indispensable in Beijing's development and thriving. Up till now, the city has built 85 reservoirs, and is the destination of the ancient Beijing-Hangzhou Grand Canal and the middle route of the modern South-to-North Water Diversion Project.