A fortress built on a rhyme could not withstand the ingenuity of tunnel warfare.
Gongsun Zan, a powerful warlord, retreated to a massive, self-contained fortress at Yijing to wait out his rival, Yuan Shao. He relied on deep moats, steel gates, and a belief that his grain reserves were invincible. He was wrong. His downfall reveals the brutal reality of ancient siege tactics.
The Battle of Yijing, fought between 198 and 199 during the late Eastern Han dynasty, pitted the 'White Horse General' Gongsun Zan against the influential Yuan Shao. After suffering a major defeat at Baoqiu in 195, where he lost at least 20,000 troops, Gongsun Zan withdrew to Yijing. He transformed the site into a formidable defensive complex, featuring ten encircling moats and a central citadel. He even installed a pulley system to communicate with his officers while remaining inside with his wives and concubines, stubbornly refusing to leave his fortress despite the mounting pressure.
Gongsun Zan’s isolationist strategy relied on the hope that Yuan Shao would eventually abandon the siege. However, this passivity proved fatal. As Yuan Shao’s forces systematically destroyed outlying garrisons, the defenders lost hope and mutinied. Yuan Shao, bolstered by Wuhuan reinforcements under Tadun, eventually reached the main gates. A desperate plan to coordinate a relief force of 100,000 troops led by Zhang Yan and Gongsun Xu failed when Yuan Shao’s forces intercepted a message and lured Gongsun Zan into a trap, forcing him back into his citadel.
The final blow came through sophisticated engineering. Yuan Shao’s sappers dug tunnels beneath the fortress, propping them up with wooden beams as they advanced. Once they reached the center, they set the supports on fire, causing the citadel and its towers to collapse. Facing certain defeat, Gongsun Zan killed his family and committed suicide by self-immolation. His death marked the end of his administration and allowed Yuan Shao to consolidate control over northern China, clearing the path for his later campaigns until he eventually faced Cao Cao in 200.
Source: Battle of Yijing
