@SomeoneElse, but Germany is only one of those countrys which have some sort of Freedom to roam which does affect the meaning of undefined access tags.
My argument would be that forcing the use of foot=yes and bicycle=yes on highway=path would actually further reduce the usability of highway=path in these countries, since there would no longer be a distinction between undefined and yes.
Can you expand on that a bit? I don’t understand what the problem is here…
for bicycle/foot/horse unset yes is the default values
, so it can not have any difference in meaning.
I see two problems:
foot=yes or bicycle=yes is already implied, people tend to use explicit foot=yes or bicycle=yes to indicate actual usability (which is wrong, but common practice). If we now change the default logic (in these countries) this might break more than it fixes.But this is 13 years practice and I would expect a new proposal to change this.
Your examples show that the standard Brouter trekking bike profile uses a cost factor of
That seems just fine to me for usage in my country, and also in parts of Germany, since I understand that
Is riding a bike in certain parts of the forest forbidden?
[…] Each Bundesland has their own rules, so there’s no general answer for all of Germany. It’s possible you are only allowed to ride on gravel roads, or on pathways wider than 2 m, etc.
Which I also read sometime ago in a German cycling magazin and is also illustrated by this example:
In 1995, Baden-Württemberg tightened up §14 of the Federal Forest Act, which generally allows bicycles to ride on paths, by introducing the two-meter rule in §37.3 of the State Forest Act BW. This prohibits cycling in the forest on paths less than two meters wide.
If you worry that a path where cycling is legally allowed (bicycle=yes only means it is legal), but which is practically not really suitable for general cycling, is being used by routers, please
Cheers.
Yes, I misunderstood what you wrote at first, sorry.
I believe that an implicit yes and an explicit yes have a difference in meaning.
The problem is that, even in Germany, it’s not an implicit rule everywhere (as noted already). It’s an assumption that you can make if you don’t have better data. It still makes sense to add an actual tag that says “yes, cycling (or walking, or whatever) is allowed here” if someone has checked all of the myriad of things (is the path in BaWu? is it <2m wide?) that might affect it.
I know, but still many routers treat those access tags the way I described above, even commercial ones:
highway=path - profile: bikehighway=path - profile: fastbikehighway=path; bicycle=yes - profile: fastbikethose examples show that Komoot does not take the 2-m rule into account which in turn means they also make a difference between implicit yes and explicit yes.
Again, I’m not saying we should care, I’m just saying that forcing the use of explicit access rules will certainly break things - just as getting rid of explicit rules in favor of implicit rules broke things as you mentioned above.
Then I guess you must believe that an implicit vs explicit value for any access tagging would differ in meaning. Seems a bit confusing. Perhaps that’s why someone recently came through my area and added bicycle=designated to all the previously mapped highway=cycleway. It seemed entirely unnecessary to me. 
We have had the discussion implicit vs. explicit several times in the german forum in regard of different tags (in most cases acess=*). The problem with an implicit access=yes (or no) is that it does not give any proof if the mapper is happy with the implicit value or if the mapper just has forgotten to check if the implicit value is correct. You do not have this problem with an explicit value. Anyhow these discussions never came up with a clear consensus as far as I remember. I believe it depends on the given situation which approach is the better one.
It seems to me that this discussion is based on different views of what “implies foot=yes / implies bicycle=yes” mean:
That is a very good argument against interpretation (b) -that prohibits tagging implied values-, but not against interpretation (a) -that is aimed at data consumers and not mappers.
If you look at the history of the proposed default values in the country-specific tables in OSM tags for routing/Access restrictions - OpenStreetMap Wiki , you’ll see changes in cases where the interpretation of the default value have changed (even if the traffic/access rules themselves have remained the same) .
When such a change in default value (from A → B, for say bicycle=* on a bridleway) occurs and you believe that this is also a rule for what to tag and what not to tag, you are left with a problem:
These problems can be avoided by being clear and explicit to your fellow mappers and data users about access tags and use as little hidden assumptions as possible.
Only consider leaving out tags when they can be inferred by definition (such as bicycle=designated on a highway=cycleway), not by some assumed default that may be interpreted differently by area, by different people, over time and per usecase.
This is the first time that I have heard of this, and I have not read this in the access-documentation either. Surely some people will act this way (I’ve seen stranger things come along), but I would be very hesitant to assume that this is a widespread interpretation internationally, since it seems to be in such clear violation of the described primary scope of the general wiki for key:access :
Access values describe legal permissions/restrictions and should follow ground truth; e.g., signage or legal ruling and not introduce guesswork. It does not describe common or typical use, even if signage is generally ignored.
I don’t think so. Komoot answered a few months back in a PM that they -based upon the OSM wiki- just assume you may ride there that when a highway=path is not tagged for bicycle=* . They don’t seem to use a penalty for a missing bicycle=yes like Brouter does.
This despite the data in OSM showing that the majority paths that are tagged for access in that state have a negative value (bicycle=no / private ).
The routing behavior was consistent with this and this was the reason for contacting Komoot after complaints by forest owners about routing suggestions over paths that are prohibited for cycling in real life, but untagged for bicycle in OSM
As noted earlier, on most paths in OSM that are still untagged for bicycle=* in my country cycling is NOT allowed, they just arent’t tagged yet.
So you can not be sure that an untagged way complies to a presumed default, the only way to reduce uncertainty is to be explicit in tags, regardless if they do or don’t comply to a default.
“meaning” is probably the wrong word, but yes, I would argue that there is almost always a difference between implicit vs. explicit. We also add source:maxspeed to speed limits (which are only implied by a road sign) because of this.
No, this is actually an argument for removing unnecessary access tags whenever possible. In BaWu, if you tag a way narrower than 2m with bicycle=no because it is narrower than 2m, then you would also have to add width=x where x < 2m, or source:bicycle=2m rule Baden-Wuerttemberg, because otherwise a change in legislation would cause a massive amount of work.
Yet another argument for keeping it implicit, because otherwise such a change would become impossible.
I fully agree that there are advantages to making it explicit, but I am not quite convinced yet that they outweigh the disadvantages.
I would love to gradually shift to a phase where highway=path becomes analogous to highway=road. This would of course require that we have a consensus about which alternative tags we use to cover most of the use cases that highway=path now fulfills.
In Austria there are 53744 km highway=path, of which
1082 km - 2% are bicycle=yes,
1928 km - 3.5% are bicycle=designated,
5465 km - 10% are bicycle=no and
45132 km - 84% are “not bicycle”=*.
That sums up pretty well, not much lost here. On how many of those paths not tagged for bicycle the implicit bicycle=yes holds?
Along the lines of the proposal process, it must hold at least in three out of four cases (75%) to find approval as a generally applicable statement, that is, at least 33849 km of path on the ground must be bicycle=yes|designated at a minimum, no matter any individual markup.
Spoiler: Out of those 53744 km highway=path:
23492 km - 44% are sac_scale=*
Of those:
192 km - are bicycle=yes and sac_scale=hiking
750 km - are bicycle=no and sac_scale=hiking
3407 km - are bicycle=no and sac_scale=*
3851 km - are bicyle=* and sac_scale=*
That makes it look like cycling is generally not allowed on hiking trails, that make up for close to half of all paths. Will the assumption that cycling is allowed on paths hold in Austria?
(Data scraped from ohsome - dashboard)
(is the path in BaWu? is it <2m wide?)
if it is width>2m and no explicit access (designated), it is probably a track.
Quaternion:
- if you explicitely state an implicit rule, what do you do if the implicit rule changes later on?
That is a very good argument against interpretation (b) -that prohibits tagging implied values-, but not against interpretation (a) -that is aimed at data consumers and not mappers.
it is not an argument against tagging, you could tag that it is implicit.
Or are they being marked bicycle=no by people that think “This is a rough walking track, so you couldn’t possibly / comfortably ride a bike along here”?
I would be very surprised if this was true. Here two fastbike examples that - in my opinion - are impossible to explain if Komoot does not penalize missing bicycle=yes tags:
Below you can see what they interpret into a 220 yd long path segment, depending on whether a bicycle=yes tag is present or not:
I have given this some more thought and what I wanted to say is: there seems to be a strong correlation between the presence of foot or bicycle access tags and the walkability or bikeability of the path - and at least some routers seem to exploit that.
I actually do both, but I also had to realize that even in Germany, which presumably has one of the highest densities of active mappers, in the world - high quality surface and smoothness data is at best wishful thinking and that probably the majority of all bicycle=no or bicycle=yes tags (which were not deduced from an actual traffic sign) are actually wrong.
It would be interesting to know how many mappers actually know what bicycle=yes is really supposed to mean.