Stone Arch Viaduct / Bridge

[railandsail]

Here are the two zones of my viaduct marked out with the yellow marks. On the right side of the dwg is the double track (2) mainlines leading up most of that side from its start down in the lower end, up to the tunnel entrance to the helix at the back wall.

The single track portion is represented by that track that that splits off of one of the double track mainlines just prior to entering the helix portal and travels along the back wall to curve down and eventually join back in with the inboard mainline down the left side of the layout. This is my 'alternative track' that allows a trains to run continuous loops around the lower level of the layout without having to climb the helix each time.

In both cases the viaduct(s) climb over two different tracks at their upper heights,...near the helix portal.
The longer double track portion climbs a 2.64% grade,... best I can do at the moment.

I'm not even going to mention the grade for the shorter single track portion at this time, as I am sure I will get many naysayers. Lets just say that I envision that in MOST cases the trains will be running down this grade, not up it.

 
Very rough mock-up at the beginning,...those blocks of wood are not the correct height
 

 
And those sheets of foamcore standing vertical are no where near correct,...just spare pieces thrown up to approx the outer reaches of the Balt city scene. And that viaduct there is an older plastic one I happen to have laying around.
(I was originally planning on letting the Balt property line come out and cover that curved track exiting/entering the back wall. but there were some problems there with incorporating the viaduct directly into that 'property line' with the city, so I thought it best to put the city line in back of that curved track. I think I will now let that curved track behind the viaduct be one that is exciting/entering the 'harbor tunnel' of Balt)