There are specific people in the military that are assigned to light the beacons when they spot invaders.
Historically, Japan invaded Joseon in 1592. The current timeline of this show. It was mentioned a couple times by Yun Tae-seok (the senior guardian general) before he was killed. Something about Japan preparing to invade their country.
It was mentioned a couple times by Yun Tae-seok (the senior guardian general) before he was killed. Something about Japan preparing to invade their country.