How to tag roundabouts

UffeKousgaard · 2011-12-05T09:07:04.000Z

I have noticed some roundabouts are tagged as “Junction = roundabout” and “oneway = true”, while others only have “Junction = roundabout”.

Strictly speaking the junction tag should be enough, but I can see the map rendering do not show the direction in that case.

Example without oneway setting:
http://www.openstreetmap.org/browse/way/78247078

Example with oneway setting:
http://www.openstreetmap.org/browse/way/328618

Which is correct?

chris66 · 2011-12-05T09:26:24.000Z

http://wiki.openstreetmap.org/wiki/Tag:junction%3Droundabout
junction=roundabout is implying oneway=yes.
So the oneway-tag is not needed.

scai · 2011-12-05T10:53:37.000Z

I guess Mapnik usually doesn’t want to draw direction arrows for roundabouts because the direction is always the same for a specific country and can thus be omitted. Yet you should always draw the way in the direction of the roundabout’s traffic flow!

UffeKousgaard · 2011-12-05T12:00:47.000Z

When the arrows are missing it is not very easy to spot an error.

csdf · 2011-12-06T06:33:37.000Z

The arrows are visible in any editing software (JOSM, Potlatch etc). And keepright (http://keepright.ipax.at) will flag roundabout errors.