Japan's 100 Famous Castles Nitta Kanayama Castle (Ota City, Gunma Prefecture) October 1st, 2025 - November 30th, 2025 Autumn Limited Edition Castle Stamp. ・Undefeated Castle ver. [The Appeal of Kanayama Castle] Kanayama Castle was built during the Warring States period. During times of war, the residence was located at the foot of the mountain, and the castle on the mountaintop was used for defense during battles. It is a distinctive mountain castle. Kenshin Uesugi attacked it five times but could not capture it, and it is known as an "impregnable castle." For castle fans and castle stamp collectors, how about it? Shipping will be waterproofed and protected from bending. 210 yen discount when purchased with other castle stamps.