I have been a fairly avid hiker for decades would like to make sure that the trails that I use are properly mapped in OpenStreetMap. As I render my own maps this is doubly important to me.

But there is some ambiguity in how this should be done.

First, the OSM terms/tags of footway and path are not really used in my dialect of English. Second, OSM tag names and values are more code words, somewhat based on UK English, with OSM.specific meanings. It might be easier if something like “h1” were used as a value rather than, say, “trunk”. Then the baggage of your own local dialect of English would not get in the way.

We have sidewalks or walkways and we have trails. While we do use the word path we don’t use footway. At least not in everyday usage.

• Sidewalks and/or walkways are usually in urban or suburban areas. They are generally hard surfaced with concrete being the most used surfacing material though compacted crushed rock bound with an acrylic binding material may be used in more “park like” areas. They are level and smooth enough that you can easily walk on them with flip-flops while pushing a stroller.
• Trails are almost always multipurpose. While hiking may be the predominant use most trails are also open to bicycles and equestrian use. Within US Federally designated wilderness bicycles are not allows but trails are usually still shared use between equestrians and hikers. Note that while bicycles are allowed on most trails, it would be folly to try to ride them with anything other than a mountain bike. In addition there are trail systems specifically set up for “off highway vehicle” (OHV) use. They are called trails but you will find dirt bikes and other ATVs rather than hikers, equestrians and bicyclists.

OpenStreetMap Wiki

With that in mind we look at the various tagging defined in the OpenStreetMap Wiki that might be appropriate.

First, of course, is looking at highways and the obvious first stop is on the section about paths. The paragraph in that table about “footways” says it “includes walking tracks”. “Walking tracks” is not used in my dialect of English. To me it might mean hiking trails or it might not. Another possibility listed is for “path” and that says it is a “a non-specific path” and it says to use “footway” “for paths mainly for walkers”.

So my first impression is that “path” more closely aligns with “trails” in the Western United States. But lets dig a bit deeper to be sure.

“Footways”

The page about footways says that it should only be “used for mapping minor pathways which are used mainly or exclusively by pedestrians.” For more major pedestrian ways it say we should use highway=pedestrian. And “for multi-use or unspecified paths and trails used by a variety of non-motorised traffic the tag highway=path may be better suited”. It further says that path can be modified with tagging for sac_scale, trail_visibility, surface and access. My feeling from reading all this is that hiking trails should be tagged as “path”.

Apparently I am not alone as I see lots of other mappers in my area use “path” for hiking trails and “footway” for paved walkways in suburban and urban areas.

“Path”

Paths are “either multi-use or unspecified usage, open to all non-motorized vehicles and not intended for motorized vehicles unless tagged so separately.” Seems to fit our local trails open for hikers, equestrians and, in many cases, mountain bikers.

So again, from my local perspective, it seems hiking trails should be tagged with “path”.

A gap in the values for “highway”

The “non-motorized” adjective rules out using “path” for OHV trails. But there isn’t an alternative either: OHV trails are usually too narrow to be tagged as a track. And if you want to be pedantic about it, “tracks” are “roads for mostly agricultural or forestry uses.” Clearly, a recreational trail is not for agricultural or forestry use.

And, from reading the tagging email list, it seems there are parts of the world where the way from one isolated hamlet/village to another is too narrow for a normal sized vehicle so they are used by motorbikes. While for utilitarian use rather than recreation this seems to be the same gap in highway values as OHV trails fall into.

But tagging abhors a vacuum and “path” seems to be the closest fit so it has been used in those cases.

In France there are bicycle ways called “voie verte”. It is apparently a wide, smooth way for bicycles, usable by regular (not mountain) bikes, but does not meet the OSM standards for “cycleway”. So they are apparently often tagged as highway=path, bicycle=yes. Exactly the same tagging as a typical hiking trail with quite different characteristics where I live.

Because there were no highway values specifically applicable for OHV trails, access to remote villages, voie verte, and probably other types of highways, “path” has been used or misused. It is now a bit like highway=“road”. It lets you know something is there, probably narrow and unpaved, but not really what it is.

Hiking in other parts of the world

My impression is that in other parts of the world hiking trails are often restricted to hiking. No mountain bike use. And, I guess, no equestrians. In those areas hiking trails are often but not always tagged as “footway”.

Other Tags

So if you want to render or otherwise process OSM data for hiking trails you need to be able to handle both “footway” and “path”. And you should be able to tell the difference between a voie verte and a Western United States multipurpose trail, even though they may be tagged the same way.

This is at least part of the issue with “path” that has been raging on the tagging email lists recently.

At present my feeling is that “path” should be formally redefined to be the narrow/not suitable for normal motor vehicle equivalent to “highway=road” and that new purpose specific highway=* values be defined for hiking trails, voie verte, OHV trails, etc.

While I want a nice resolution to this, my immediate goal is to be able to render trail distances on my maps given the tagging that is currently being used “in the wild”. So lets look at other tags that are often, but not always, found on hiking trails. The hope is that we can disambiguate hiking trails from other things.

sac_scale

The Swiss Alpine Club (SAC) scale wiki page was poorly translated into English. My impression from the photographs and descriptions are that only two values make sense for the trails worth rendering: “Hiking” and “mountain_hiking”. The other, more difficult classifications say things like “the treadway may not be visible”. In my mind, if the treadway (trail) is not visible then it is not a trail. In my part of the world that would be classified as “off trail hiking”. But, for use in deciding if a footway is a paved walkway or a hiking trail the simple existence of this tag could be a clue.

trail_visibility

This tag comes from the same people that created the sac_scale tag. Again, it has some values that confuse me. “Horrible” is defined as “often pathless” and “no” is defined as “mostly pathless”. As above, if you can’t see the trail then in my mind it isn’t a trail. Still, the presence of this tag strongly indicates we are dealing with a hiking trail.

Informal

The “informal” tag seems to be widely misunderstood. I recall the threads on it in the tagging list and from that it seems clear to me: It is used to mark a trail that is not officially sanctioned by the land manager.

If I recall correctly, it came out of trying to create an official map for a California state park where they had “social” or “Desire” paths that they were trying to close off and restore back to nature. And they certainly did not want shown on an official path.

But OSM maps what is on the ground and if the land manager removed the trails from OSM they would immediately be re-added some mapper. The solution was to mark the trails as “informal” and also put a “access=no” tag. The informal tag allowed their renderer to ignore the trail. The access=no would, they hoped, keep OSM based apps from routing hikers past their piled brush barriers and over the illegal trail.

Anyway, for my purpose the “informal” tag is only seen on trails so if a way has it then it is highly likely that it is a trail. Maybe not one the land manager wants me to use, but it is a trail.

Surface

Surface is a horrible tag. Not because the concept is bad but because the range of values in use. On the good side, there are some fairly common values that can help distinguish between a walkway (hard surfaces like “paved”, “concrete” or “asphalt”) from a hiking trail (soft surfaces like “dirt”, “ground”, “sand”, “unpaved”). Of course there are some ambiguous values too.

Access

It seems to me that access can be used as a negative indicator. If a “path” has a “foot=no” tag then it is likely the path is for something else, possibly it is a OHV trail. But I have never seen this value on a path in the wild.

Name

At least where I am, very few suburban walkways have names but many trails do. In addition, most of the named trails have a suffix of “Trail”. So a way tagged “highway=path”, “name=‘Overlook Trail’” is likely to be a trail. This is, of course, a regional thing and not likely to be expected around the world.

Putting it together

A final wrinkle

A lot of the local “wilderness parks” have only recently been retired from being ranch land. And a lot of the designated trails were four wheel drive access roads. “Tracks” in OSM parlance. I want to treat these a bit like hiking trails, that is show distances on them. But I don’t want to show distances on all tracks. Fortunately I can use the “foot=” tag to detect that.

The decision tree

Based on all that, my current decision on whether a way is a hiking trail or not is currently:

Wouldn’t it just be easier if they were tagged as highway=hiking_trail? It wouldn’t be hard to convert all the local trails from highway=path and it would be easier for non-outdoor types to map a hiking trail.