[Tagging] How to tag: Legally separated ways

Alberto albertoferraris at fastwebnet.it
Mon Oct 15 17:55:33 GMT 2012

> > a) One way with lanes=4
> > b) Two separate ways with lanes=2 each
> > c) Tell me!

a) because distinction between physical and legal barriers is important.
Ok in that picture there is no much difference, but as Simone pointed out,
for long roads there is a big difference: if any router can't distinguish
between physical and legal barrier, it will not suggest to emergency vehicle
to cross the line, and it will tell them to do a long alternative trip
instead. This is a big problem, because when you are driving the GPS shows
you only a little portion of the route and you may not understand
(especially in emergency) that you can shorten the route simply crossing the
Moreover if we accept solution b) we should tag every road with continuous
line in the middle as two separate roads, one for each direction.

>Additionally to the lanes=4 and oneway=yes you could put a divider-tag on
the way http://wiki.openstreetmap.org/wiki/Proposed_features/Divider
>even if it doesn't explicitly tell you where the divider is placed you
might be able to infer it from the following ways (at least in this case).

+1 We can improve this proposal, to make clear where the divider is placed.

Alberto (Viking81)

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