Original post from the first version of this thread:
sac_scale is the global standard on OSM for describing the difficulty of moving over terrain for trails/paths/wilderness ways/etc. This isn’t ideal as mappers in areas that don’t use SAC aren’t familiar with it, and users that come across it don’t really know what it means. I can mentally map T1-4 pretty easily, but don’t feel like I have a good grasp on where the lines between 4-6 would be (and to be fair, there will never be a 100% consensus, but having been on trails rated a certain way would help).
Two possible approaches I can see to this:
1 - create some universal keys that map to different localized systems
It seems like adding some sort of
osm_scale (inspired by @Hungerburg) that maps onto various regional ratings systems would be useful. sac_scale would still exist as is. This isn’t necessarily what I would propose for this osm_scale, but it’s an example of the concept.
I was spitballing in the failed highway=scramble thread to try and come up with a cross-cultural set of buckets and came up with:
highway=path - what any person able enough to walk and moderately fit is capable of doing.
Class 1 YDS, SAC T1-2, Austria Blue, SWW Yellow, CAI T & E
highway=demanding-path - might need hands for balance, or require some upper body strength (I guess a ladder or mantle would fall in here?) but you’re not climbing rock or have any significant direct exposure. having some experience hiking is highly recommended, but you don’t need to be a climber.
Class 2 YDS, SAC T3, UAII 1, Austria Red, SWW White-red-white, CAI EE
highway=scramble - requires use of hands to pull yourself up terrain. it’s generally simple climbing that is done without a rope but may be uncomfortable to people without technical experience and have fatal consequences. While far simpler than technical climbing, having climbing experience will help greatly. No extra equipment (like ropes, harnesses, etc) is expected to be used. Simple Via Ferrata routes with anything complicated than a ladder or a railing would probably fall into a scramble due to technique and physical strength required?
Class 3 YDS, SAC T4-6, UAII 2, Austria Black, SWW White-blue-white, BMC Grade 1, Schall Scale A, Hüssler Scale K1
2 - Add different rating systems for different countries
Have keys for the the British scrambling system, Austrian numbers, US YDS, the sales with umlauts in them, CAI, etc. Mapping applications would have to support this, but many mapping applications are region specific (AllTrails, Gaia, Caltopo in the US. OsmAnd, LocusMaps, etc in Europe). There’s a Russian system for rating passes in there already.