Haikyo means “ruin” in Japanese. It’s often used to refer to the exploration of abandoned buildings and ghost towns. There are plenty of haikyo locations all over Japan. My favorite haikyo blogger has been all over Japan, especially the Kansai area (Osaka, Kyoto, Nara, Tokushima!!!). He goes out of his way to find really cool and unique places to explore.
I, on the other hand, did not have to go any bit out of my way to find a haikyo site along Kumihama Bay. There is an abandoned hotel towering over the whole landscape. It was begun to compete with the many minshuku guesthouses in the area. However, funding ran out midway through construction and the site was left as is. It was easy to enter, well lit, and not very spooky.