Thanks Dave--yep, full circle.
Hiding the switches will be easy. Where the train splits from the front edge of the layout to the back--going to have to punch a hole "under" the highway--cool tunnel portal opportunity. I am going to try and work in "Bird Creek" in the extra space formed by the turnaround area, and the mountain rise I the back ground should hide the switches (access from underneath in case of issues). Here is a picture of Bird Creek:
