Work in progress - spent two long play sessions covering the entire Main Line, Ffarquhar Branch, Harbour Lines and the Ballahoo Loop "on foot", using the waypoint feature to measure distances between locations and annotating all the gradient posts. Took some time, but the actual diagram is now coming along nice and quick thanks to all the data I've assembled. Will post ongoing updates here - any feedback is really welcome!
With the diagram taking clearer shape, here's another look at the western half of the Main Line. The sea level and elevations I worked out by working back from Knapford Harbour, where I estimated the rails on the quayside to be about ten feet above the water. Feedback on this would be really welcome.
This is great! I have been interested in some route learning on Sodor, however the lack of a sectional appendix makes things a little difficult. Sodor has some interesting local rules given that trains can chase each other through signal blocks and even change routes without the signallers knowing! All this gradient data will be very useful, and perhaps one day you could publish the official rules of the Island of Sodor.
Hah! I doubt I'll go that far - I try to work on the assumptions of the Rev. Awdry, that Sodor conforms to real railway working practice. And here's how the diagram currently looks!
