RFC: hiking_technique key (or a better name!) to describe movement on paths by hikers

Here video on Austrian scales, English subtitles available, the pictures should be telling - Wandern: Wegeschwierigkeiten verstehen | Sicher Bergwandern | Episode #4 - YouTube - They try to be funny: The guy with the cheese is from Vorarlberg where blue is the hard trail, the guy with the pipe is from Tirol, where blue would be the easy trail, which is marked very rarely though.

Mapping Austrian colour to values above:

  1. blue
  2. red
  3. black
  4. Alpine Route icon

I’m surprised how clean that maps. Maybe I did not read thoroughly enough?

Classification saw some shift in recent years. What was red 30 years ago might be black now. I’d say, that comes from growth in public, in order to adapt to changes in abilities and desires. Alpine route was only introduced recently to make black less open-ended and sort out legal issues. Meanwhile this class has spread to other parts of Austria.

Thanks, I’ll go over it and update. It does map pretty well to a number of systems - it deals with clear “real world” impacts related to the level of technique people need to move over terrain and there’s been a lot of similar thinking. There’s a decent chance someone could use this properly without looking at the wiki which can’t be said for most other systems - while the key values are human movement centered I tried to keep things “verifiable” by focusing on the terrain/obstacles that cause different types of movement.

You’ll recognize the bones of this from your scramble thread, it lives on!

It’s interesting how “casual” ratings tend to be easier than the past, while “technical” ratings keep on getting harder and harder. YDS was supposed to stop at 5.10 because it was the hardest thing a human could climb, and now we’re at 5.15d or whatever. I figure if people want more granularity for scramble they can just add whatever local system they want on there. hiking_technique=scrambling + bmc=3 or sac=t6 or whatever. All that is for nerds and doesn’t need to be in a general rating. :stuck_out_tongue:

I’ve updated the main post, but I’ll copy it here too.

Links to different rating systems

YDS & Bouldering


NFS Trail Classifications (loose and not 100% predictive for higher grades)

SAC & friends






https://www.cai.it/wp-content/uploads/2021/12/allegato-circolare-22_2021-Classificazione-difficoltà.pdf (pdf in Italian)

bielointothewild.com - bielointothewild Resources and Information. (good unofficial write up)


Tasmanian PWS

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CAI (unofficial, couldn’t find anything on the CAI website)

there is docu in the wiki:

on the cai website there is (found it with a search engine, not on the website): https://www.cai.it/wp-content/uploads/2021/12/allegato-circolare-22_2021-Classificazione-difficoltà.pdf

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Thanks, the wiki wasn’t loading for me when I was writing this up. I’ll edit the links up top. I guess it’s not surprising I didn’t pull up a PDF in Italian from my own search results. :slight_smile:

I like the idea very much in general of redesigning what we use as “hiking difficulty”. Still this (on the lower end) for me has the same problem that the current sac_scale has.

For the casual hiker SAC T1 and T2 are too broad, there is a lot of detail within it that we could pull from other tags, but which might also warrant splitting up the values 1 and 2 into further values.

My idea would be something like this (for splitting the Value 1 in your proposal):

Value 1: Easy walking:

Description: The ground is mostly smooth. Very small obstacles might exist, but they are very easily visible, and easily circumnavigated. When walking you need to pay pretty much no attention to the terrain. The path is useable by everyone, including people not that sure of walking and strollers. Might require hiking footwear when the weather is bad.

This would mostly be used on track_type=1 or 2 tracks, or paths that are about NFS class 4 or 5. This is very much on the low end of SAC T1

Value 2: Walking

Description: The ground is slightly rough. There might be some smaller obstacles (bigger rocks within the ground, some overgrowth), but they don’t require a serious effort to circumnavigate. Obstacles aren’t higher than shin height. Keeping a bit of attention to the terrain is important, but taking a look around for a couple of seconds while walking isn’t a problem. Likely not useable by people that are unsure of walking (small toddlers, seniors that require a walking aid), using a stroller is probably not possible. Hiking footwear recommended when the weather is bad.

Typical usage would be track_type=3 or 4, maybe some track_type=5, many smaller forest paths. In NFS classification this is a “wilder” class 4 or a class 3. We are about in the middle of SAC T1.

Value 3: Hiking

Description: The ground is fairly rough. Small obstacles (smaller rocks, overgrowth) appear often/continously and need to navigated. Bigger obstacles up to about knee height might be present, but can still be navigated mostly without stopping to check where to take the next step. Continous attention to the terrain required. Certain amount of surefootedness is required, so smaller children and seniors likely shouldn’t take this path. Terrain might get fairly muddy on bad weather, but hiking gear is recommended in general.

This might get used on some heavily overgrown/low usage tracks with track_type=5. In the NFS system this is class 1-2 with some harder class 3 mixed in. We are still within SAC T1, even though this might start to pass into SAC T2.


Today I learned something about the Austrian classification that I’d like to mention here:

Imagine, you are a tour guide. There are two licenses - hiking guide and mountaineering guide.

A hiking guide may only guide tours on paths classified red at most.

If you want to guide tours over routes classified black, you need a mountaineering guide license.

The difference between red and black is specified: If you trip on a red way and stay completely passive, you fall at most 30 m. It will hurt but it likely will not change your life for the rest of it. Otherwise, it is a black route.

Why not just propose a new key austrian_class=*? We generally use a key containing “scale” for difficulty, but if it is called Austrian Classification, perhaps we should stick with a key related to that.

A scale is what is used for classification :wink: BTW, we already had dav_scale (for the blue/red/black system), even though easy to tag – just copy from the guidepost dot – it languished. If it can be made complicated, why go the easy way?

Why not just propose a new key austrian_class=*? We generally use a key containing “scale” for difficulty, but if it is called Austrian Classification, perhaps we should stick with a key related to that.

I would prefer to stick to “scale”, there are already sac_scale and cai_scale, why not an öav_scale :slight_smile:

I think your use cases make sense, but I worry that’s getting a bit too granular. Having been on trail a lot this summer in a few different places (Canadian Rockies, Olympics, and Eastern Sierra) I’ve been pondering in the back of my head how to better word some of this.

I think perhaps having my casual_walking and then merge your walking and hiking into into walking and then have my surefooted walking would make sense. I can see a lot of ambiguity between the amount of obstacles (and relative height) in your 2 and 3 values.

I think the main break down would be:

  • casual_walking no to very few obstacles - very little attention needed, pretty anyone that can walk can do it safely
  • walking some obstacles you can step around - occasional attention required, while there isn’t meaningful challenge for most people small children or people with impaired movement (elderly, injured, certain diseases or conditions, etc) can struggle
  • surefooted walking obstacles you cannot step around - this gets into T2, you cannot avoid stepping on an uneven surface and while experienced hikers will not find it difficult it could be hazardous for certain groups.
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That’d fall more into fall risk / exposure than hiking_technique.

On a tangential note, there was some brief discussion on having things be a way or node. Vey short sections that bump up difficulty of movement should probably be tagged as stairs or obstacle=*.

On a very well used trail (part of a famous short backpacking loop, and used by fisherman, day hikers, and other backpackers many dozens of people a day in the summer) there’s more of those f$%#king stock steps. My partner’s feeling on them:

That section could be tagged as stairs and is a bit clearer as they cover the entire path.

Here’s a different section of the PCT with mellower stonework

Nearby there’s some simple T2 / hard T1 terrain for a brief period. There’s often rocks filled in areas that get a lot of water / would erode out (or are just rocky), but these tend to be fairly localized.

You also get naturally occurring obstacles that act similarly. These should probably just be marked as nodes vs part of the way.

It looks like I can’t update the original post anymore, so here’s updated values for the T1 - T2 range of hikes.

updated: 2023-10-26, downgrading use_of_hands to hands_for_balance. You can see the original one in the first post, I’m basically just dropping mantling to keep it more consistent. I’ve also tweaked requirements a little bit.

It looks like I can’t update the original post anymore, so here’s updated values for the T1 - T2 range of hikes.

Value 0: unverified walking


This value would exist for data ported over from the existing sac_scale T1, as the trail could be either casual walking or attentive walking and that would need to be done manually later.

Value 1: casual walking


Falls under: Class 1 YDS, ~NFS Class 4-5, SAC T1 / Yellow, Austria Blue, CAI T, AWTGS Grades 1, PWS W1 & W2

Obstacles: The ground may not be entirely smooth and have some irregularities, but it has few obstacles and they tend to be smaller or have a large amount of space around them. It isn’t uncommon for these trails to use imported materials for their surfaces, but can also be on compacted or naturally even ground.

Slope: Flat to moderate.

Typical Requirements:

  • Be able to casually walk. Casual walking paths that wheelchair accessible should be tagged with wheelchair=yes. In generally people will mobility issues, need to use a walking aid, or are very old or young can safely traverse this terrain.
  • Almost all casual footwear will be adequate.
  • Little to no focus needed for traction, people can walk and talk and not pay much attention to the path surface.

Value 2: attentive walking

Falls under: Class 1 YDS, ~NFS Class 2-3, SAC T1 / Yellow, Austria Blue, CAI T, AWTGS Grades 2, PWS W1 & W2


The trail has some ankle to knee high obstacles like roots or rocks, but these can almost always be walked around and it’s possible to walk on an even or nearly even surface.

Typical Requirements:

  • Be able to walk in a coordinated manner and avoid obstacles. People that need to use aids when walking, or have some kind of issue that impacts their mobility can have problems in sections.
  • Sneakers or other casual footwear should be fine barring specific terrain like mud etc.
  • Focus occasionally needed for traction, people can walk and talk at times but will need to look at their feet.

Slope: Flat to moderate.

Value 3: surefooted hiking


Falls under: Class 1 YDS, NFS Class 1-3, SAC T2 / White-Red-White, Austria Red, CAI E, AWTGS Grade 3?, PWS T1-T2

Obstacles: The path has around ankle to knee high obstacles (roots, rocks, etc) that need to be stepped on / passed through to proceed forward. It’s common to have long stretches of trail that are on uneven surfaces.

Slope: Generally flat to moderate.

Typical Requirements:

  • Able to walk with balance, coordination, and sure-footedness.
  • Footwear is more consequential but lightweight but outdoorsy shoes like trail runners or approach shoes should be perfectly fine, flip flops and high heels will be awkward or unsafe. People with bad ankles or that lack experience may want traditional mid or high top boots.
  • Attention will need to paid to footing in places to avoid loss of traction or tripping.

Value 4: hiking while using hands for balance


Falls under: Class 2 YDS, NFS Class 1-2, SAC T3 / White-Red-White, UAII 1, Austria Black, SWW White-red-white, CAI EE, AWTGS 3-4?, PWS T3-T4?, BMC Grade 0.5?

Obstacles: This ground that is uneven or steep enough that it’d be reasonable to expect people to occasionally use their hands or trekking poles for balance while hiking. If talus isn’t so large you need to climb over it, but it’s larger than in surefooted_hiking and you need to put a hand on a piece here or there to support yourself it falls into this category. Note that while this type of terrain is commonly talus, it can also be steep enough slopes of any surface.

Slope: Even flat terrain can have obstacles on it that require use of hands to surmount. Additionally once terrain gets close to or over 30° hands (or trekking poles) are generally used for support and balance as the slope itself becomes an obstacle. Nearly all highly developed trails are explicitly designed to avoid such steep angles, but there are exceptions.

Typical Requirements:

  • Along with being surefooted, you need a stronger sense of balance and coordination than on surefooted_hiking terrain.
  • Footwear with grippy soles meant for hiking is recommended (boots, approach shoes, etc).
  • The ability to think a few steps ahead and a little bit of confidence when focusing on the path are very helpful. :slight_smile:

Value 5: Scrambling


Falls under: Class 3-4 YDS, Bouldering VB, NFS Class 1, SAC T4-6, UAII 2, Austria “Alpine Route”, CAI EE, AWTGS 4-6?, PWS T3-R?, BMC Grade 1-3

Obstacles: High angle obstacles that need to be “climbed” for significant lengths of time finding handholds and footholds and pulling oneself up, but are simpler than technical climbing which use of a rope and harness are expected (see grading systems above). Feet are off the ground for more than a few moves, or there are repeated sections of short climbing. This is going to be a slim minority of paths in many regions.

Slope: Generally moderate to high angle.

Typical Requirements:

  • Physically fit, being able to pull up a decent portion your body weight with upper body strength.
  • Approach shoes, “high route shoes”, cross trainers, or boots are recommended. You’ll generally want either more traditional boots with “structure” or a lightweight shoe that conforms to the foot for better feel and independent use of foot muscles for control.
  • While not considered “technical climbing” significant risk can be involved. Previous climbing or mountaineering experience is highly recommended.

The classification you’ve come up with so far seems more useful across a wider range of paths and trails than sac_scale. I know you added “hiking” to the key to narrow the scope, but I actually think this scale looks applicable to any path regardless of whether it is considered hiking or not. casual_walking looks like it would accurately describe most sidewalks and paths in urban parks. Lots of paths exist in slightly wilder municipal parks that require attentive_walking, but people out for a quick dog walk on these trails probably wouldn’t say they are hiking. I think this is great because the hiking and mountain_hiking values of sac_scale have always felt quite wrong for these types of paths. Perhaps the key name should communicate that this is a classification of technique/difficulty for walking, traveling on foot, pedestrian mobility, etc (including but not limited to hiking). Some ideas:

  • walking_technique - not so good since the top end of the scale becomes scrambling, not walking
  • pedestrian_technique - doesn’t feel like the right wording for the higher classes
  • foot_technique - a bit more abstract, but matches other uses of foot in OSM tags

The _technique suffix seems a bit of a mouthful, though it is specific. _scale or _class as a suffix would be more general, but I think would work just as well. horse_scale and via_ferrata_scale appear to be already in use.


Bravo, looks very good! I would support this if it could be used from scratch. However, we already have hiking classification schemes. How do you propose to move from them to this one without too much resurvey needed? Would it be suitable for automated editing?

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If you look at the “Falls Under” it maps to SAC pretty evenly aside from splitting T1 into casual and attentive walking. I added in unverified_walking for T1 to account for that - it could then be switched to whatever is more appropriate (casual or attentive). T2 and T3 should map cleanly and T4-T6 are collapsed into one value.

There is a larger issue of SAC not being well understood so there being some bad data in there (or values boosted for exposure). That bad data still exists whether it’s mapped to this or not. This system feels more intuitive so should have less of that going forward, and mapping it to regional systems helps clarify it to some extent for people familiar with existing international systems.

I would imagine that this would create less confusion in the future, and existing misuses of SAC would be more easily corrected.

That would make sense to me. I come from a mountaineer-lite perspective so thinking of how “technical” something is drew me to technique - mostly to avoid “difficulty” which can mean many different things.

foot_scale or something similar seems the best choice, there’s also a mtb_scale in use. pedestrian makes me think more of the walking end of the scale. It sounds a little weird, but everything else I’m thinking of is even weirder.

Technically scrambling isn’t really foot as it uses all four limbs, but scrambling is niche. I would envision people putting whatever technical scale is local alongside it - YDS, BMC, SAC, UAII, etc for more clarification for those that actually care while keeping the key simpler for 99.9% of everyone else. :slight_smile: If this eventually does get migrated we’d have existing T4-T6 there anyways for more detailed information.

Before attentive_walking existed (which got added due partially to @F_Weinmann’s very detailed post and noticing myself a gap when hiking this summer on trails) surefooted_hiking was just surefooted_walking, but I renamed it to break it away from the two walking levels under T1 in terms of being able to migrate this cleanly.

Some of the ideas around strollers and walking aids and how they impact obstacles are directly from the post mentioned above. :slight_smile:

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I need to doublecheck the mappings for casual_walking and attentive_walking actually - I just copied them off of the old walking and then split NFS trail classification ratings, but it’s been enough time I don’t remember the details of some of the other systems.

I haven’t had the time to go through all the current related topics and think it all through. But before I forget it, here is small nitpicky comment: The SAC scale uses the labels “typical terrain and possible difficulties” and “requirements”. There, the requirements are fairly broad, so “requirements” fits. The terrain in the SAC scale is more specific and, thus, they write “typical” and “possible”. Here, you mention, e.g., “Enough upper body strength to pull up your body”, which may be necessary some times, but not other times. So I would also label it as “typical requirements” or “range of typical requirements” or something similar.

Apart from this: Thanks for putting all the effort in pursuing this!

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