Ask a resident what the most unique structures in town are and they'll likely mention Kaikyo Yume Tower. It's one of the first things you'll spot when you start your sightseeing.
This modern piece of architecture is located in Shimonoseki. Once you've seen everything you want to at Kaikyo Yume Tower, check out nearby Karato Fish Market, Mojiko Retro, and Kokura Castle.