Six ancient cities built one on top of the other over 2,000 years unearthed in central China

Chinese archaeologists have unearthed six underground cities – one on top of another – from several dynasties spanning more than 2,000 years in central China.

The ancient cities, believed to have been built during the Warring States (475-221 BC) to the Qing dynasty (1644-1911) periods, were excavated at the Xinzheng Gate site in Kaifeng, Henan province, on Saturday, the People’s Daily reported.

Kaifeng is one of China’s oldest cities and was the Chinese capital in several dynasties.

As the area sits on the south bank of the Yellow River, after wars destroyed the city in the past, floods from the river would bury the ruins under mud, and a new city would eventually be built on top.