Quote Originally Posted by Reg06
Nomadic, I was unsure about that channel. I'm not sure yet if it was a naturally formed channel (does that even happen? Presumably it would have once been a river that went nearly from coast to coast but erosion/mudslide/earthquake finished the channel), or if it was a river that was extended by human hands. Could it have formed naturally?
It is possible that it is an extended river though in it's position that would be rare. the huge amount of rock that would have to be cleared away to breach the other side. Remember the high side is likely going to be a good ways above sea level and even a couple hundred feet above would make it exceedingly expensive (and thus probably not worth the effort). Erosion wise rivers do switch directions, and thus it could punch out the other side. However this type of river isn't one I see doing that (if it did reverse direction you would probably be much more likely to wind up with an interior sea).

It could be a natural channel created by rifting plates (two plates pull apart and water fills in between them). In this case though you will want to widen the channel and add irregularities to it so it looks like two pieces being broken apart.