Waves and bores of the onrushing Qiantang River tides hit onto an ancient dam in Haining City of east China's Zhejiang Province on Monday, forming fascinating scenes.

On Monday, the tides were seen approaching and reaching the Tashan Dam in Huangwan Town, the earliest dam built on the Qiantang River, with a history of over 200 years. Galloping tides hit against the dam, after which waves either kept moving forward or retreated, amazing the onlookers.
The height of the one-line tidal bore reached about one meter.
The Tashan Dam is a T-shaped embankment that spans over 600 meters. As the first long T-shaped dam on the Qiantang River, it is where the tidal bore begins to show its most impressive display.
The tidal bore is mainly caused by the gravitational pull of the moon. The centrifugal force produced by the rotation of the Earth and the trumpet shape of the Hangzhou Bay in Zhejiang makes it easy for the tide to come in, but difficult to ebb, thus giving rise to the largest tidal bore.
The Qiantang River is known for the world's largest tidal bore, featuring four common types of tidal bores: criss-cross tidal bore, one-line tidal bore, back-flow tidal bore, and fish scale tidal.
The tides usually reach their peak on the 18th day of the eighth lunar month.