What, with Ickybukero?

For the rail fans, Saga has the Chikugo River Lift Bridge https://en.wikipedia.org/wiki/Chikugo_River_Lift_Bridge. It is pedestrian only these days.

Shimabara is connected-ish to Kumamoto by a ferry https://www.japan-guide.com/e/e4451.html and a few buses/taxi if you're a pedestrian.