Talk:Key:sac scale

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Please see the proposals discussion page for the history of this key.

Fixed rope route (Klettersteig)

Discussion move to path Talk:Tag:highway=path

Using SAC_SCALE for some tracks to distinguish hikability?

I think it should be possible to use the sac_scale also for tracks. Many tracks (forestry use) in Austria are marked and designated also for hiking and the sac_scale=hiking should apply. Some 4-wheel drive/tractor use tracks may qualify in some parts for sac_scale=mountain_hiking. Main reason: Distinguish tracks that are made for hiking from other tracks. One could create a hiking map by including all ways that have a sac rating. In my case the whole mountain behind my house is covered with tracks, gravel roads in the forest of grade2-grade5 only a few links inbetween are paths. To indicate that the track is part of a hiking route the sac_scale should apply. Any thoughts or comments?

Nah, that defeats the purpose. Already right now sac_scale=hiking is a mess where you don't know at all what to expect. If there is a hiking route on a track, than create a relation for that hiking route.--Extremecarver 19:04, 6 October 2009 (UTC)
I suggest you use extension tags on your highway=track to show it is not a "common" track (if common means usable by a passanger car) For exemple : surface=* or/and smoothness=* or/and tracktype=* sletuffe 01:24, 11 October 2009 (UTC)
The idea is to tag some (definitely not all!) tracks for hiking so it may be recognized as hikeable track by a renderer focusing on a hiking map. If tracks are not marked as hikeable a renderer cannot distinguish between city area tracks and tracks commonly in use for hiking. This distinction works fine for (foot)paths it could also work for tracks.
Okay, I think I missunderstood. I though you wanted to show technical hikeability of tracks. Which, even in city area are hikeable. What you want looks like to emphasis tracks that are of interest to hikers ? If yes, the above comment by Extremecarver to create a route that joins several pieces of track/path/highway is a good solution. Or if the track is of interest but is not really part of any named/important route, don't do anything, the map representation of tracks and path is enough to show wich track connects nothing or which track lead to somewhere. sletuffe 14:58, 11 October 2009 (UTC)
I have still some objections: In my area there are hiking trails that include segments on residential roads, tracks and actually the minority of trails is of type path (because the farmers drive with tractors to fetch wood the paths all end up as tracks). In the forest areas there are only 5% paths and 95% tracks. 50% of the tracks are hiking trails with hiking signs. About one third(!!) of the tracks are dead end forestry roads that should be mapped but not associated with hiking. How would one distinguish a "Holzweg" (forestry road that is often a dead end) from a hiking way-segment? One could use the presence of a sac_scale tag as distinction that the path is part of a hiking network and that it leads somewhere. But maybe we should discuss a hiking=yes tag and a mtb=yes? I personally would reserve the "route" for hiking ways that have at least a name and that are long distance. How would one associate a sac_scale with a route if the included ways have different scales? Katzlbt 09:49, 14 November 2009 (UTC)
I understand the need, but don't feel it's the best way do deal with it. Because that would be using a hiking rating scale for something that is different from it's difficulty scale. However you'r hiking=yes (or preferably something more explicit) seams better to me. The dead end track case could left as is, as this is guessable directly from the data. An hiking_interest=no could still be add though sletuffe 14:02, 14 November 2009 (UTC)
I am looking for something positive to tag a track that has a hiking reference number. I agree that dead end tracks can be managed by an algorithm, though Osmarender cannot do that in XSLT. Katzlbt 21:30, 23 November 2009 (UTC)
BTW, there are definitely tracks that I would tag sac_scale=mountain_hiking for a fall hazard or inclination.Katzlbt 09:49, 14 November 2009 (UTC)
This is a completly different matter, that need comes much much closer to the existing use of sac_scale. Also I wonder what type of track could have fall hazard ! I still think a few track could compete for a sac_scale=hiking tag. But I'm not sure it's the best way to tag terrible tracks, other ideas welcome. sletuffe 14:02, 14 November 2009 (UTC)
I hiked a track grade5 close to 100% incline; on the one side you do not want to go off the track or you are dead (especially in the dark). The track was marked with a hiking number and I assigned mountain_hiking for suggesting good shoes and not taking kids there. The sac_scale serves as rating how easy the track is hikable and that it is a marked hiking way. How would you tag a hiking way that goes on a track and that has a hiking reference number? I am open to suggestions. Example: name=Hikingway, tracktype=grade3, highway=track, mtb:scale=0, ref=23 (hiking), mtb:ref=47, mtb:name=Magic Moutain Runde ;-) and ...? How could we tag the way to let a renderer distinguish it as marked hiking path? Katzlbt 21:30, 23 November 2009 (UTC)
I checked in the original text of SAC. It does not imply any kind of way but talks about inclination. So a "Weg" that is a track with steep inclination qualifies for mountain_hiking right away. The German "Weg" also means track not only path. sac=hiking is flat or slightly inclined and for sneakers. Specifically sac_scale=hiking says that you do not need a map to hike such a way. SAC Scale So from the original text SAC scale applied to tracks is no misuse at all.
Ad discussion of this topic in our local OSM group yielded that sac_scale should apply to tracks (although only the 2 lower rankings: hiking and mountain_hiking). A often seen pattern in the Alps is that a destination can be reached by foot as mountain_hiking (steep sloped track or path) and also as hiking on a forestry road alternative.


Osmarender displays sac_scale=hiking in red. Citation developers: It is not a bug. It is intended this way. Katzlbt 07:10, 3 December 2009 (UTC)

Real world use

Is this revised SAC scale actually in use somewhere outside of OSM? I was hiking in Graubünden last week and both the maps and the signs use the old scale. Which of course is not so strange if at least 95% of all hiking paths around there would fall into the T1 and T2 categories. --Cartinus 10:37, 20 June 2010 (UTC)

Revised? I do not see that OSM's SAC scale is revised. But, yes 90% of all hiking ways fall into the first 2 categories.
AFAIK most paths in the BAW Bündner Wanderwege network will have either yellow or red-white-red lozenges/paint markings, and correspond to SAC 1 and 2. There are relatively few blue-white-blue trails (mainly in the National Park, for instance from Val Trupchun to Chamanna Cluazza, and I think the trail to summit of Piz Quattervals). Other routes to commonly ascended 3000ers are either only partially waymarked, and then usually with cairns (steinmaenner). Examples: Fluela Wisshorn N ridge(T4+/T5 or WS according to SummitPost), Fluela Schwarzhorn (T4 on SummitPost, seems overgraded, I'd have expected T3-), Piz Minschun (T4 perhaps), Piz Lischana (T4 for summit section). The SAC scale is for me a huge improvement over the old EB/BG grading as it gives a much better idea of what I am likely to encounter on the route. The scale is widely used on the web (e.g., SummitPost) and in many recent (last 5 years) books. SK53 14:00, 22 July 2010 (UTC)
Your reply and the more recent edits to this page confirm what I was getting at with my question. This tag is useless for most hikers. This should have been made clear from the start so people could have ignored it in stead of mistagging a "difficult" hike. As to the word revised in my original question: I didn't wrote the osm-tag was revised. The SAC scale itself was revised, it used to have three categories like the three colours in the tag description and the three line styles on most Swiss and Austrian hiking maps. --Cartinus 19:22, 16 December 2012 (UTC)

Hiking grade

I agree that the scale is a mountaineering scale, not a hiking scale. Hiking trails are pretty much all T1/T2, with a few T3-. At the low end, we might have something like:

  • Easy - Mostly level, no significant elevation gain, treadway well compacted, any walker can likely manage.
  • Easy+ - Not flat, but grades typically no more than 500 feet/mile (10%). No significant fall hazard, or rock scrambling that cannot be handled simply by stepping up.
  • Moderate - Grades 500-800 feet/mile (10-16%), inclines too steep for an unconditioned city person to handle comfortably. Typically no or minimal rock scrambling.
  • Moderate+ - Average grades fall in 'moderate' category, but challenging features (rocky, rooty, or muddy treadway; talus; water crossings; brief sections of higher grades) warrant a higher rating.
  • Strenuous - Grades in excess of 800 feet/mile (16%), significant rock scrambling, or challenging terrain (boulder fields, loose scree, wet trail, etc.) Limited exposure (typically less than a 3-metre fall) may be present.
  • Difficult - Sustained (multiple hours) steep grades or rock scrambles. Grades may exceed 1000 feet/mile (20%). Difficult fords. Fixed cables, chains. or ladders may be present. Rock scrambles may need hands for more than balance and require upper body strength to make progress. Leaping may be required. Shorter hikers may be at a disadvantage. Lethal exposures may be present.

All of these would fit within T1 and T2, with the exception that 'difficult' might cross over into T3. The grading of a trail might also be seasonal; I know of trails that are 'strenuous' in summer but require technical gear (and are therefore beyond what most would call 'hiking') in winter. A scale like this might avoid the problem of bringing Grandmother or the toddler on a 'moderate' or worse trail. While there is some room for judgment, objective criteria are offered. -- ke9tv 19:35, 8 April 2019 (UTC).


I cannot find what the "Yellow - red - blue color scheme" is for. Is it used on Swiss Alpine CLub maps? SHould this be described on the wiki page? Thanks Mayeul 18:36, 16 December 2012 (UTC)

I have no ideas, maybe some maps edited by the SAC ? Whatever, I think we shouldn't talk about it on the page. Wiki pages are about tags, not how to render. Or only as a side note to say : "it is rendered here and there this or that way". sletuffe 19:16, 16 December 2012 (UTC)
Those are the colours used by the SAC on the signs. If you want to make that more clear in the text, be my guest. Just removing the info is not helpful. User:Cartinus
Okay. I just tought it wasn't bringing more information than the table juste bellow (duplicate information). sletuffe 19:52, 16 December 2012 (UTC)

controversy about verifiability

I've added a section about the controversy about this tag (Mainly because it is listed at verifiability). Those who want to propose solutions to that problem are welcome to talk about it here. sletuffe (talk) 18:06, 19 February 2015 (UTC)