Castle

城 - "Shiro" (or oshiro) means castle, but when it is appended to a name of a castle, it is pronounced "jō." Such as Kaminoyama-jō in the above example.

Also, if you're Okinawan, you would be familiar with this kanji because many Okinawan names have it. For example, Oshiro, Miyashiro, Kaneshiro, etc. The kanji can also be pronounced "gi" as in Miyagi (think Karate Kid movie).

Place: Kaminoyama Castle, Yamagata Pref.