I think as a general rule, if an area is blocked off by a traffic cone or a construction sign, it means it's a WIP and will be added eventually. Don't expect it to be too soon though, some areas have been blocked off for quite some time without updates - the Urotsuki head in Flesh Paths World and the dark path in the Flooded City are 2 of the older Coned off areas that come to mind - I'll have a look at the map in RPGmaker and see what's down there (if anything)
EDIT: Okay, well it leads to a small winding passage with pillars running over it before it reaches the side of the map. The map doesn't loop around, and there aren't currently any event triggers anywhere past the cone in your screenshot. I would think that that passage will probably lead to another area of the town in a future update, but the folder deserted town is in doesn't contain any unused or empty maps, so I would assume the Dev in question hasn't started on it yet and it's probably not going to be done for a while. WHOO ASSUMPTIONS