The Qiantang River (also known as the Qian River) is a southeast Chinese river that originates in the borders of Anhui and Jiangxi provinces and passes through Hangzhou, the capital of Zhejiang province, before flowing into the East China Sea through Hangzhou Bay. The river and bay are known for the world's largest tidal bore, which is up to 9 metres high, and travels at up to 40 km per hour. The tide rushing into the river from the bay causes a bore usually from 1.5-4.6 m high, which sweeps past Hangzhou and menaces shipping in the harbour.