Photo by Cao Cao's Underground Military Tunnels - Ancient Map Exhibition Board

Cao Cao's Underground Military Tunnels - Ancient Map Exhibition Board

Photo by Cao Cao's Underground Troops' Tunnel - The Bozhou Textual Installation in Front of the Red Wall

Cao Cao's Underground Troops' Tunnel - The Bozhou Textual Installation in Front of the Red Wall

Photo by Cao Cao's Underground Military Tunnels - Take a photo with Chinese architecture and inscribed stone tablets.

Cao Cao's Underground Military Tunnels - Take a photo with Chinese architecture and inscribed stone tablets.

Photo by Cao Cao's Underground Military Tunnels - Group Photo with the Night View of the City Tower

Cao Cao's Underground Military Tunnels - Group Photo with the Night View of the City Tower

Photo by Cao Cao's Underground Military Tunnels - Take a photo with the railings and multi-storied pavilion buildings.

Cao Cao's Underground Military Tunnels - Take a photo with the railings and multi-storied pavilion buildings.

Photo by Cao Cao's Underground Military Tunnels - Qiao Wang Tower Steps

Cao Cao's Underground Military Tunnels - Qiao Wang Tower Steps

Photo by Baozhou Cao Cao's Underground Troops Tunnel - Before Gongxue

Baozhou Cao Cao's Underground Troops Tunnel - Before Gongxue

Photo by Bozhou Cao Cao's Military Tunnels - Outer Balustrade of the Qiao Wanglou Corridor

Bozhou Cao Cao's Military Tunnels - Outer Balustrade of the Qiao Wanglou Corridor

Photo by Bozhou Cao Cao's Soldier-Transporting Tunnel - Qiao Wanglou Corridor Outer Leather Drum

Bozhou Cao Cao's Soldier-Transporting Tunnel - Qiao Wanglou Corridor Outer Leather Drum

Photo by Baozhou Cao Cao's Soldier Transport Tunnel - Stone Rail Steps

Baozhou Cao Cao's Soldier Transport Tunnel - Stone Rail Steps