Hangzhou (Chinese: 杭州; Hangzhou dialect: ɦaŋ tsei; Mandarin pinyin: Hángzhōu Mandarin pronunciation: [xɑ̌ŋtʂóʊ] ( listen)), formerly transliterated as Hangchow, is the capital and largest city of Zhejiang Province in Eastern China. It is governed as a sub-provincial city. As of 2010, the entire administrative division ("shì", 杭州市) or prefecture had a registered population of 8.7 million people. The built up area of the Hangzhou municipality had a resident population of 6.242 million in 2010 (urban and suburban districts), of which 3.56 million lived in the six urban core districts.

A core city of the Yangtze River Delta, Hangzhou has a position on the Hangzhou Bay 180 kilometres (110 mi) southwest of Shanghai that gives it economic power. It has been one of the most renowned and prosperous cities of China for much of the last 1,000 years, due in part to its beautiful natural scenery. The city's West Lake is its best-known attraction.

The celebrated Neolithic culture of Hemudu inhabited Yuyao, an area (now a city) 100 kilometers south-east of Hangzhou, as far back as seven thousand years ago when rice was first cultivated in southeastern China. The area immediately surrounding the modern city of Hangzhou was inhabited five thousand years ago by the Liangzhu culture, so named for the small town of Liangzhu not far to the northwest of Hangzhou where the ancient jade carving civilization was first discovered.