In the side of the main gate you may see some holes that have been made in the structure. This is a remnant of the Battle of Okinawa when the Japanese forces attempted to build a moat around Nakagusuku Castle.

However, while trying to build this moat, they realized that the structure was built so solid, it proved difficult for the equipment they used to penetrate the walls. If they had more time they may have been able to accomplish this feat, but the approach of the American army was growing near. In the end, they gave up making Nakagusuku the main base for the war.

This is not, however, a story detailing how strong the castle itself is. Thanks to this decision, the structure of Nakagusuku avoided becoming a battleground. Starting with Shuri Castle, many of the castles on the island became battlegrounds, and the original structures were destroyed in the aftermath of the war. However Nakagusuku was able to preserve its original structure from long ago. These holes prove how lucky this castle was