Dadun Platform Site

　　In ancient times, platforms known as "dun tai" were established at strategic locations to transmit military messages — by lighting fires at night and smoke signals during the day. During the Ming Dynasty, to defend against Japanese pirate invasions, a network of beacon towers was set up with the city as the command center. The function of these platforms was to monitor for enemy movements; upon spotting an approaching enemy, soldiers would light wolf smoke as an alarm. Each platform was manned by five soldiers on rotation, but by the mid-Qing Dynasty, they gradually fell into disuse.

　　In Jilin Province, notable dun tai sites include the Dadun Platform Site, Xiaodun Platform Site, and Ma’ershan Platform Site. These three sites form a triangular military communication system, supporting each other strategically. Given the technological conditions of ancient military communication, the design of this early warning system and its effective use of the terrain remain truly impressive even by today’s standards. The overall layout curves in an arc, protecting the fertile river valley basin between Yanji City and the confluence of the Buerhatong River and the Hailan River, forming a remarkable ancient military defensive complex.