Photo: tom-spring, Public domain via Wikimedia Commons
Contrary to the name, this area contains very little in the way of castle ruins, offering just a small section of stone wall that was once used to fortify the small castle. The reason to go is not for the (non-existent) castle, but for the best view of Nanao and its bay. The small park at the top is peaceful, and the view is gorgeous. The best time to go is in spring on a clear day.
Nanao Castle was a Muromachi period yamajiro-style Japanese castle located in what is now the city of Nanao, Ishikawa Prefecture, in the Hokuriku region of Japan. Its ruins have been protected as a National Historic Site since 1934.
© OpenStreetMap contributors
石川県七尾美術館
Nanao was the birthplace of Tohaku Hasegawa (長谷川等伯), who was a well known Japanese master painter. They have annual exhibitions related to his works. You can also see many local artists' works there. Worth checking out if you have some free time.
石川県能登島ガラス美術館
This museum is the only public specialized glass art museum in Japan. It displays some unique glass sculptures based on original ideas from artists such as Picasso and Chagall. It also has some interesting sculptures and a section devoted to old liquor bottles once used in Japan. If that wasn't quirky enough, the building looks like a ship straight out of Star Wars.