The Jiadantu site in Chonqing: An example of Southern Song mountain fortress defense

Perched on Diaoyu Mountain in Hechuan district, Chongqing, Diaoyu city was a critical pillar of mountain fortress defenses during the 13th-century wars between the Southern Song Dynasty and the Mongol troops.

In 2024, new archaeological discoveries at the Jiadantu site in Diaoyu city revealed five city gates, four sections of walls, three terraces and three ancient roads. Among them, the Qinghua Gate stands out — the first-ever Southern Song ring gate found at Diaoyu city, forming a clever double-walled defense system with surrounding walls and terraces. Archaeologists also uncovered a wealth of ancient weapons and even a Mongol army assault tunnel.

These finds fill in a gap in Diaoyu city's mountain fortress defense system and provide a textbook example for studying similar Southern Song system in the Bashu region.