Hi all, very interesting subject for this month.
Not sure if I be able to enter as not been well for a long time.
Something I been working on before that may or may not be good idea for underground railway system. So thought this be a good place to show you and see what you all think.
I made a bridge that just looks like a normal UK Road.
These 2 images give you an idea .. the one on left just some railway line and trains. To right it what these bridges look like. No pylons just the road and paving to match what you would get in a town.

- Subway Overpass_01.png (35 KiB) Viewed 5773 times
This one is using Overlap objects Parks I created some time ago to see if my idea will work.

- Subway Overpass_02.png (25.35 KiB) Viewed 5773 times
Vehicles drive across the bridges as if ordinary roads.
Hope later if this idea is worth continuing on with is to create overlaps with buildings on them but there are so many Town sets .. what buildings and from which set I should use. Or maybe I just use some of my town houses I made before.
If you like to try for yourself with what ever GRF sets you normally use. ere a copy of my bridge set. The GUI are not done as not been able to concentrate on new coding for now. Hope one day soon to finish it.
The Road Bridge is called "Subway Overpass Bridge" The Rail bridge with that name is wooden bridge .. I yet to change it to something else.
I'll put the source over in my "AuzBridges" forum if any one like to fiddle around with it.