Liangzhu, the “Venice of the Stone Age,” fell after unprecedented rains overwhelmed its advanced water systems

A new study reveals that extreme flooding caused by intense monsoon rains led to the collapse of Liangzhu, an advanced ancient civilisation along the Yangtze River delta, around 4,300 years ago. Known as the “Venice of the Stone Age,” Liangzhu was one of the earliest highly-developed communities to base its infrastructure on water management systems.

Located about 160km southwest of Shanghai, Liangzhu boasted an intricate network of canals, dams, and reservoirs, supporting year-round agriculture. The city, recognised as a UNESCO World Heritage Site in 2019, showcased technological and cultural sophistication for its time, particularly in agriculture and aquaculture. However, despite its ingenuity, the civilisation abruptly declined, leaving its ruins abandoned.

Published in Science Advances, the research combined archaeological evidence with ancient climate data extracted from stalagmites in nearby caves. The findings indicate that the Liangzhu culture collapsed during a short but intense wet period between 4,345 and 4,324 years ago.

“These caves have provided precise insights into the climatic conditions at the time,” said Christoph Spötl, a co-author from the University of Innsbruck, Austria. Stalagmite samples revealed unusually high precipitation levels that likely caused severe flooding of the Yangtze River and its tributaries.

A thin clay layer found on the city’s ruins suggests that flooding from the Yangtze River or the East China Sea played a role in the civilisation’s downfall. The researchers found no evidence of human causes, such as conflict, for Liangzhu’s abandonment.

According to the study, the anomalous rainfall overwhelmed the city’s sophisticated water management systems, rendering them unable to protect against the massive floods. This led to the destruction of the city, forcing its inhabitants to flee and marking the end of the Liangzhu culture.