That’s another good point, as well as considering the variance between levels and “may exist” or “probably exists” of different aspects. Some NFS 1 trails in SEKI get enough foot traffic they’re pretty followable, others (upper Wallace creek) look like a NFS 3 trail for a mile or so and then basically disappear for the next mile or two aside from brief periods of a hundred feet here or there. Heck the trail up to Dragon Lake which is abandoned (NFS 0?) is basically NFS 2/3 once you get above the initial granite at the bottom of it.
I think it’s useful meta-data, but I agree that it doesn’t answer the desire for knowledge of:
- how visible a trail is, e.g. ease of following / likelihood of getting lost on it
- presence of obstacles / uneven footing, for people with a lack of experience (or carrying heavy packs), that are older, have mobility issues, etc
2 is increasingly how I’m seeing “difficulty” and why despite YDS not being used on trails it came to mind when thinking of mapping various international systems. Most map clients can tell someone the distance and (rough, depending on how you smooth it, etc, caveat) elevation gain between two points on a trail, so that aspect of “difficulty” seems less useful (and honestly more subjective) than just describing aspects of the terrain and how people move over it.
update: at the bottom of this page is an interesting system, the German (Bergsteiger Magazine) system, which consists of four different axis:
- Endurance. (elevation gain, length)
- Power. (obstacles and technique)
- Psyche. (exposure)
- Orientation (trail_visibility)
Organizing them by the attributes one needs vs the actual thing itself is an interesting take, and not one I really agree with (power could just as easily and probably more accurately be technique), but it makes sense to me. Breaking things down gets you around those cases where a path fits into multiple categories (and one doesn’t know which attribute was chosen to the detriment of others).
Endurance is basically covered by modern mapping technology that can spit out total distance and approximate elevation between two points on a way.
Power is the difficulty/mobility/technique issue that I’m taking a stab at.
Psyche… I don’t think OSM requires an exposure rating system for paths honestly. It’d be pretty niche, but as I’m typing this I’m thinking of some formal NPS trails that require psyche. Hmm. Maybe later.
Orientation I think due to differing local norms this is best done by regional tags. Perhaps they use the same basic values, but can describe them differently? Say there’s always an excellent, good, poor, bad or whatever but what constitutes those can vary by region?