[OSM-talk-be] Conventions for Old Railway Lines / Towpaths

[Ben Laenen]

Kenny Moens wrote:
> Hello guys,
>
> When looking at the maps in the Antwerp area, there are some differences
> in the way the old railway lines/towpaths are mapped. All these routes
> are typically restricted for bicycles and pedestrians (sometimes horses,
> sometimes motorized with permit). On the other hand, they are sometimes
> mapped with "highway=cycleway", while others are mapped with
> "highway=track" with the necessary restrictions to not allow other traffic.


After mapping a lot of different paths with all possible kind of traffic signs 
I've developed a tagging method which is no longer using subjective terms like 
("suited for bicycles", "used by a lot of cyclists", etc).

I'm currently only mapping highway=cycleway when the path is really a 
cycleway, which means that it either is marked on the ground with long broken 
lines, or with a traffic sign D7 or D9, because otherwise it's not a cycleway. 
90% of cycleways are thus found next to a road, but sometimes you see them on 
some other paths as well (usually because the ones in charge of traffic signs 
placement don't know about signs like F99a, or the signs were put there before 
those F99* signs were added to our traffic code)

All other paths aren't a cycleway, so they become highway=path if there are no 
cars, motorcycles or agricultural vehicles allowed (or when they aren't 
physically able to drive there) (btw, I normally discard the fact that 
sometimes there are paths where certain people with a license are allowed to 
drive there in a car ("uitgezonderd vergunninghouders" along the Albertkanaal 
for example), so that stays a path and doesn't become highway=unclassified)

That only the paths which are really a cycleway are tagged highway=cycleway 
here may be different from past tagging methods -- I used to tag something 
cycleway from the moment bicycles were allowed. I also conveniently 
disregarded other vehicle types in that process... Because a moped is allowed 
on cycleways, and when one tags a paths with C3 ("no vehicles allowed") with 
the extra sign "except bicycles" as cycleway, a route planner would think 
mopeds are allowed on it as well. So that was obviously not the right way to 
tag, and when the highway=path tag was added it opened the door to finally tag 
things correctly.


Anyway, my main highway tag usage goes as follows:

* cars, motorcycles or agricultural vehicles allowed (and able to drive 
there)?
** road surface is concrete, asphalt or cobblestones → highway=unclassified
** otherwise → highway=track
(I know some Germans sneaked highway=track to be used for some paved roads as 
well into the wiki, but I don't like track for paved roads :-) )

* no cars etc. allowed:
** sign D7/D9/D10: → highway=cycleway (with D9 and D10: add foot=yes, D9: add 
segregated=yes, D10: segragated=no)
** sign D11: → highway=footway
** sign D13 (still need to see that sign somewhere in real life) → 
highway=bridleway
** all else: highway=path

and then add the tags for each traffic sign.

The F99a/b/c are a problem though, since they're actually a special kind of 
road, like a "woonerf", "autoweg" or "autosnelweg", and just like those they 
have a list of implicit traffic rules. Choosing between the highway tags isn't 
difficult: F99c becomes "residential", "unclassified" or "track", and F99a and 
F99b become "path". (I've seen an F99c which was a meter wide though, so 
"path" is possible with F99c as well apparently, although it would allow some 
motorized traffic like mopeds if it can drive there -- and when he's allowed 
to drive there of course as there are other conditions for that as well). 
Currently I add a tag like "traffic_sign=F99a" (so it can be detected later 
when a good tagging method appears) and for each icon on the sign I add 
"foot=yes", "bicycle=yes", "horse=yes" (F99c implies "agricultural=yes"). 
There's currently a proposal about a designation tag 
(http://wiki.openstreetmap.org/wiki/Proposed_features/Designation) which could 
solve this.

Second unsolved problem: paths like those in some nature reserves, parks or 
other public domains. They usually don't make use of traffic signs, but do it 
with their own set of signs. So access tags can be a problem there I think, 
but usually it's highway=path though.


Anyway, this is my idea about how to tag things, and it seems to work quite 
well with the paths I've mapped, removes ambiguity, both in knowing afterwards 
what's allowed or not, and the tags are also no longer subjective to the 
person mapping it, so everyone would tag the same.

Ben