Windmill Observatory, a place where you can overlook the Genkai Sea, is adorned with rapeseed flowers in spring.

The Windmill Observatory was originally a battery completed in 1936 along the northern coast of Kyushu to strengthen defense. At that time, four cannons were installed on Oshima, but they were removed without ever being used in battle. The foundation prepared for the battery still remains here and can be seen today. Surrounding the battery ruins is the Windmill Observatory, the highest point on Oshima. The red windmill on a small hill is very striking, and from there you can overlook the Genkai Sea. In spring, there are rapeseed flowers, in summer, sunflowers, and in autumn, the area is filled with cosmos flowers. Address: Oshima, Munakata City