Viaduct with rails on top

There is a viaduct in town, rails run on top of it. The viaduct is mapped as a building=yes. Rails only appear, where the viaduct is interrupted - most often there is no building mapped, where streets cross under the railway, not even bridges at times.

https://demo.f4map.com/#lat=47.26912&lon=11.40339&zoom=19&tilt=30
https://osmbuildings.org/?lat=47.26912&lon=11.40339&zoom=19&tilt=30

Can the rails go on top?

You can try to give OSM-Renderers a hint with the layer-tag to decide which feature is “upon” or “below”.

As far as I know, a viaduct is not a building, my guess would be either bridge=viaduct(https://wiki.openstreetmap.org/wiki/Tag:bridge%3Dviaduct), or man_made=bridge (https://wiki.openstreetmap.org/wiki/Key:man_made) or both.

you could even add railway:bridge on the same polygon.

having a photo might help :slight_smile:

It seems you’re trying to model it though, however there are no plans to do that on man_made stuff (see https://forum.openstreetmap.org/viewtopic.php?pid=787470#p787470))

So you’re probably in a pinch. for F4Map, railway are drawn on the tiles, so will not appear above buildings or structure.

We might render them in 3d in the future (and bridges and tunnels), but not for now.

The mapping as of now is mixed, some stretches even show windows in osmbuildings (where there are levels coded).

Digging a bit, what renders, and how. Bridges do not show in neither rendering. Building with min level makes for the most correct rendering. But I guess you are right: The Viaduct is not a building in the osm sense of the term :wink:

Here a foto of the scene, some of the compartments are open for pass-through streets

Most viaducts should definitely be mapped as man_made=bridge + bridge=viaduct. I can see the argument for treating this particular one as a building, though, seeing how most of the arches appear to have been walled shut and converted into shops or other rooms.

If the viaduct is mapped as a building, I would tag the rails with location=roof and an appropriate layer tag.

The Berlin Stadtbahn, at least parts thereof, are “building=viaduct”. I found nothing in the Wiki on the tag. f4map shows buildings - https://demo.f4map.com/#lat=52.5230019&lon=13.3635897&zoom=19&camera.theta=45.286&camera.phi=-0.286 - A case of/for tag as you like? Or bad style, like “building=bridge”, when the “houses” can be removed without altering the “bridgeness”? Not expecting more of an answer than already given: This is not the tagging ML.