Just north of the ruins of the Dazaifu Government Offices, near a sign pointing right to the Autumn Forest (秋の森) and left to the Spring Forest (春の森), I found this mound rising up out of a pond. I immediately thought, is this a kofun? Or is it just a natural topographical occurrence?
Granted, I didn't exactly investigate. If there is a sign somewhere on the other side of the pond from where I shot this photo, I have no idea; I didn't go over there. From here it looks like it's attached to the far side of the pond, i.e. that it's not an island. It also doesn't look to resemble a keyhole shape, and strangely enough (unless I'm looking at the wrong location) I don't see it at all on Google Maps satellite view, let alone labeled.
So, bizarre question, but does anyone know if this is a kofun?