Siege of Ryūgasaki
1545 CE.
Shown on the map at 35.989°, 137.977°.
The 1545 siege of Ryūgasaki was one of many battles fought by Takeda Shingen in his bid to control Shinano Province during Japan's Sengoku period. The fortress was a satellite castle of Fukuyo, and was held by Tozawa retainer Yoshinaga Mitoyoshi. Yoshinaga himself was killed in battle while the fortress fell.
Text from the Wikipedia article Siege of Ryūgasaki, licensed CC BY-SA 4.0.