Tongji Weir
"Guyan" refers to Tongji Weir of Water Conservancy Irrigation Project.As the first batch of world irrigation project heritage, it is the core of scenic spot.Built in Xiaoliang Tianjian in the Southern Dynasty (AD 505), it is the oldest large-scale water conservancy project in Zhejiang Province.
The weir is composed of an arch dam, Tongji sluice, channel, Shihan, Yecave, general sluice and ponds.Bihu Plain is higher in the southwest than in the northeast, with a drop of 20 meters. The weir was built according to its geographical situation. Built at the highest elevation in the southwest of the Plain, its dam cut across the Songyin Stream and diverted water into the canal, basically realizing the self-flow irrigation of farmland in the Plain.
"The land under weir will always be fertile".Tongji Weir is an immortal masterpiece in the history of China's water conservancy project.It is more than 1000 years earlier than the Irchi Dam built by Spanish in the 16th century and the Bondardo Dam built by Italian in 1612. So it is one of the oldest water conservancy facilities in the world.And it is also a key cultural relics site under the state protection and a great innovation in the history of China and even the world. In 2014, it was listed in the first batch of World Irrigation Project Heritage List.