Mifune Town (御舟町) is located in the center of Kumamoto prefecture in the Kamimashiki district/county (上益城郡). The town has a population of only 17,888 people as of this writing. (No telling how many kappa--the green river imp playing the drums--there are, though.)
The biggest event in the town is the Mifune Gahppa Festival (御船があーっぱ祭り) held in August, the symbol of which is a statue of kappa called Funatarô.
Also of interest in the town is the Mifune Dinosaur Musuem. An alternative design of Mifune's manhole covers feature a dinosaur named Funeppi.
More on Mifune Town here.