The kind that it passable by bikes and pedestrians but not cars?
If it has a name, then use the name. Do not use the name of the ways around it.
i.e. If it’s Shvil Israel that goes under road 6, then both sides of the “tunnel” are named Shvil Israel, but the tunnel isn’t.
Sometimes these passages have specific names, so it’s reserved to them. Otherwise they are unnamed.
The same with the tag “ref”: Do no use the ref of the surrounding ways, but add the ref tag if it has a specific ref.
And all of the above applies to bridges as well.
No matter what way the bridge is part of.
Bridges should have specific name and ref.
talkat.
Sorry. What I meant is how do I tag it?
Tunnel?
layer=-1
Most of these ways are also tagged with tunnel=yes
I’m not sure this is a must, but it’s more apparent on the map, and isn’t a very big mistake.
talkat.
from http://wiki.openstreetmap.org/wiki/Key:tunnel
tunnel=culvert applies on underground waterways/streams passing through a culvert. Usually a pipe but in some countries, it can be very similar to a bridge (and prefer bridge=culvert if the road is reusing the same structure). Don’t use this for open-top culverts.
tunnel=culvert isn’t supported yet by Mapnik, so the way is not drawn, and it looks odd.
They way is still there, and maybe other renderers would draw it.
You can leave it asis. It’s not a mistake.
But I would suggest to use tunnel=yes and a note tag that it’s a culvert, and the value of tunnel should be changed once there’s wider support for it.
talkat.