The houses of Takeda and Tokugawa fought against each other at this site during the Sengoku (Warring States) Period. This castle was once famous as an impregnable fortress.
It has a wonderful atmosphere in the early evening. Unfortunately, the castle itself is gone, but you can feel Japanese history in a quiet place surrounded by nature.
You can also enjoy a hike there. Wearing sneakers is recommended because of the long stone stairs.