A military maze beneath Bozhou

Above ground, Bozhou’s old streets organize movement between gates, shops and courtyards. Beneath them, the Hefei University of Technology account describes a tunnel network centered on Dayu Shou, the old city’s central junction, with passages extending in several directions. “Cao Cao troop tunnel” is the site’s familiar name; the account dates its beginning to the late Eastern Han and says much of the surviving structure was rebuilt in the Song period.

The passage is not a single untouched relic. The university account places its beginning in the late Eastern Han and describes extensive Song-period rebuilding. Arched brick vaults, different bonding methods and repaired walls show a structure altered over time. The sequence matters: a route first associated with the Han period continued to be maintained and reshaped by later builders.

The documented plan includes single lanes, parallel passages, upper and lower levels, and intersections. At turns, barriers, walls, traps and trip devices complicated movement. Small “cat-ear” recesses could hold one to six people, while a command center near the central junction is described as a more elaborate space. These details make the place legible as an engineered system: it channels, divides and conceals movement rather than offering one long underground avenue.

Finds listed by the university platform include clay projectiles, thunder stones, iron blades, arrowheads, lamps, mirrors, pottery, porcelain and inkstones from Han, Tang and Song contexts. The platform also says flooding in the thirteenth century led to partial burial. Together, objects and repairs reveal a layered urban site rather than a tunnel that can be assigned to one commander or one moment alone.