I'm in the same situation and have been looking at all the manufacturers that I know of and have found nothing other than R1 and R2 curved bridges.

I have tried using straight bridges, but if they have handrails or high curbs, the longer passenger cars get caught up on the inside of the curve at each joint or rub the outside of the curve in the middle of the bridge. You need a really wide bridge to overcome this. I have the same issue with the long Jaegerndorfer Railjet coaches on an R2 bridge and had to remove the handrails.

A German gent built a stone arch viaduct himself.

The body is made of plywood, the curves are also made of very thin plywood which he put in water to bend it into shape.

http://www.railroad24.de...nbahn/forum.php?id=14544

Maerklin R3 = 515 mm / 30°. The supplier Luetke offers a 30° plate girder bridge for a 553,9 mm radius curve in H0 scale. Maybe adaptable via kitbashing?

http://www.luetke-modell...1648-1649-1898-1902.html

I once built a single track curved stone arch bridge by carving arches into styrofoam and covering the result with random ashlar texture sheet from Scalescenes (www.scalescenes.com) printed on plain heavy paper.


Another time I used Peco LK-10 Plate Girder Bridge Sides (bent into shape after resting in warm water for several minutes) and 3 mm cardboard for constructing a double-track curved bridge.

https://www.peco-uk.com/...T_ID=3323&P_ID=17264