[Talk-GB] Tagging UK Parallel crossings - Zebra for cycles

[Jacob Nevins]

[re-sent after subscribing to mailing list -- sorry if you see 2 copies]

James Derrick writes:
> After a cycle survey of the newly completed Rake Lane roundabout in North
> Tyneside, I've updated the map but wondered about better tagging for
> Parallel Crossings. This roundabout is heralded as being "Dutch Style" and
> it is good - just a shame the drivers don't know the law! :-(
  [...]
> Location:
> https://www.openstreetmap.org/?mlat=55.02405&mlon=-1.48095#map=19/55.02405/-1.48095&layers=N
> The cycle parallel crossings are mapped as separate points for routing as
> there are cycle give_way and oneway restrictions.
  [...]
> Zebra + `bicycle=designated` is functionally correct, but is there a better
> way please? Anyone familiar with Oxford or Birmingham examples?

I fished out some docs about your scheme (assuming this matches what was
actually built):
<https://my.northtyneside.gov.uk/sites/default/files/web-page-galleries/Rake%20Ln%20-%20Billy%20Mill%20Ln%20rounadbout.jpg>
<https://my.northtyneside.gov.uk/category/1564/rake-lane-billy-mill-lane-roundabout>

I think the closest to that in Cambridge (i.e. with unsignalled
ped-and-cycle-priority crossings) is the Fendon Road roundabout:
<https://www.openstreetmap.org/node/7773880586#map=20/52.17931/0.14892&layers=Y>
<https://www.cyclestreets.net/location/148655/>
<https://www.cambridgeshire.gov.uk/residents/travel-roads-and-parking/transport-projects/cycling-pedestrian-improvements/fendon-road-and-queen-edith-s-way-roundabout>
<https://therantyhighwayman.blogspot.com/2021/06/fabulous-fendon-road.html>

...but whoever tagged it chose crossing=uncontrolled for the cycle
crossing, which fails to fully capture the cycle-priority nature of the
crossing. So now I have the same question about how to tag an
unsignalled cycle-only crossing where cyclists have priority :)

For these sorts of junction systems, it does seem usual to tag the foot
and cycle crossings separately, e.g. these CYCLOPS (signalled)
junctions:
<https://www.openstreetmap.org/#map=19/53.46765/-2.25758> (not me)
<https://www.openstreetmap.org/#map=19/52.22185/0.11204> (me)
I think that's right, for the reasons you state. So if we are to show
priority for cycle-only crossings, we do need a way to tag it.

crossing_ref=zebra does feel like a bit of a bodge for a cycle-only
crossing in the UK, depending whether you take 'zebra' to denote the
official definition in the Highway Code etc (which is explicitly about
pedestrians), or the physical appearance. Might still be the best option
currently?

Looks like someone did try to come up with a scheme for explicitly
tagging who has priority at a crossing, but it turned out to be
complicated, and was abandoned:
<https://lists.openstreetmap.org/pipermail/tagging/2020-December/057071.html>
(see also followups)

Here for completeness is an isolated parallel crossing in Cambridge.
<https://www.openstreetmap.org/node/9514771833/history#map=20/52.21754/0.10385&layers=Y>
<https://www.cyclestreets.net/location/114080/>
Apparently I chose a single node (which seems OK here) with
crossing_ref=parallel; as others have noted, crossing_ref=tiger also
exists, and is more popular in taginfo, both inside and outside the UK:
<https://taginfo.openstreetmap.org/keys/crossing_ref#values>
(although personally I still think 'parallel' makes more sense, both
inside and outside the UK).

I've no idea what if anything routing engines such as CycleStreets do
with all this. (I suspect this page is not fully up to date:
<https://www.cyclestreets.net/help/journey/osmconversion/>)