I hadn't planned to make this video, but after my last one I decided to build a curved viaduct to carry the line back past the little port and on to the front of the layout. Deciding to do that was the easy part. making it a reality involved quite a lot of brainwork and I thought I would share what I learned and how it turned out.
The website I mentioned that helped jog along my memories of O level geometry is http://www.mathopenref.com/arclength.html