(Chinese Academy Of Social Sciences)

The city is between 4,300 and 4,500 years old, dating it to some time in the Longshan period, which saw the emergence of late Neolithic societies.

Now, six intersecting tunnels that functioned as a hidden transport network have been found in the most recent round of excavations.

(Chinese Academy of Social Sciences and the China Archaeology Network)

One photo shows a partial map of the passageways. Other photos show a tunnel entrance and a view inside the well-preserved arched tunnels.

The tunnels are between 5ft and 20ft beneath ground level, and range from 3ft to 6ft tall. Several of them even passed under the city's ramparts and opened up to the outside world.

According to Sun Jinsong, director of the Cultural Relics and Archaeology Academy of Inner Mongolia, the moats and defensive perimeter walls (known as barbicans) were the focus of the most recent research.

Not a bad escape route if a neighbouring kingdom has decided to attack...

This article was originally published on 21 January 2024

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