Somewhere out of the way; in the middle of nowhere; desolate. See boondocks.
"Where the hell are we?"
"I don't know, some backwater hick town. I can't find it on the map."
A place where minds have stagnated by a process of floating on one's Back and being baptized under-Water.
If you find yourself lost in some backwater town, don't try to reason with the natives. This could hurt their minds and provoke an attack.