Mapping turbo roundabouts

OpenStreetMap Questions and Answers
#1

As far as I can tell the OSM wiki page on junction=roundabout ( https://wiki.openstreetmap.org/wiki/Tag:junction%3Droundabout ) does not mention channelized roundabouts, a.k.a turbo roundabouts ( https://en.wikipedia.org/wiki/Roundabout#Turbo_roundabouts ), which are growing like mushrooms in some parts of Europe.

Lanes in such a roundabout are spiraling out. It is normally required for a driver to chose the correct entering lane based on the desired exit. Usually it is not possible to make a full circle, i.e. to exit on the same road as entered - but there may be exception for some of the approaching roads.

It would be nice to add a section to the above page, explicitly stating the preferred way of mapping such roundabouts. Are these roundabouts at all?

#2

You need to distinguish the original Dutch type with physical separation between lanes (so they are often drawn as separate lines), and eg German ones with road markings only. I have seen a few of the former.

I believe this is only a matter of effort in micro-mapping. If someone has the time, they are welcomed to increase their level of detail in the spirit of iterative refinement.

UK has spirally marked roundabouts only. Circle physical center islands, not angled as in turbo-roundabouts.

#3

FWIW the UK does have one turbo-roundabout (in Bedford), but it’s a bit of an aberration and no-one really likes it.