Kochi Castle
Kochi Castle was built by Yamauchi Kazutoyo, the first feudal lord of the Tosa domain. It was first built in 1601 after ten years of construction, and unfortunately lost to a fire in 1727. The castle you see today was reconstructed in 1753. Kochi Castle is one of 12 since the Edo Period that still has its original castle tower, and is the only one that keeps both its original castle tower and main Honmaru Palace hall. The entire 15 buildings across its grounds are registered as a National Important Cultural Asset.
I've visited so many Japanese castles, and honestly, they all look pretty similar. If you're not really into Japanese history, it's mostly just a good spot for photos.