Fukuoka is one of my most favorite destinations in Japan, it is easy to explore, very relaxed and a welcome break from the busy life of Seoul. I’ve been there a handful of times, I want to go back soon!
For me, the best things in Fukuoka include: Kushida Shrine, Fukuoka Castle, Fukuka Tower (and beach), Ohori Park (with a very swish Starbucks), Fukuoka Art Museum and the Fukuoka Asian Art Museum.
Within a short train journey you can get to Kumamoto which is a very quaint and relaxed city, shrines and sites also ready to explore.
On my next visit, I want to check out the hot springs with my partner.