Reply to "6X16 Layout with Tehachapi-Style Loop"

With more scenery and structures.

I raised the interior terrain inside the spiral loop to 2" in elevation, with the track climbing around that at 3%  from 0" to 7" at the peak.

So there are three levels to the layout, the base at 0", inside the loop at 2", and the upper level loop going from 7" to 9" at about 1% grade, to allow clearance and access to the tracks under the mountain at the left element.   The mountain is a fourth element, with the narrow gauge 5-6" above the level of the O gauge, and then the mountain peak above that, at about 18-20".