Pistes de fond dans le jura: ce qui reste à mapper

L’Espace NordiqueJurassien partage le tracé des pistes de ski de fond depuis l’espace pro de sa carte interactive (carte dispo ici ).

Ces tracés sont d’origines diverses, et il ne fait pas sens de les copier dans OpenStreetMap. Cependant,cela permet une comparaison, et on peut voir ainsi que près de la moitié des pistes de ski de fond du Jura français ne sont pas mappés dans OSM ! Sans surprise, les coins les plus courus et les plus enneigés sont mieux cartographiés que les autres.

J’en ai fait une carte qui permet de savoir ou poser vos skis cet hiver pour compléter, c’est ici: OpenStreetMap.org et EspaceNordique Jurassien: Pistes de ski nordiques manquantes dans le Jura

Parmi les sites les plus mal servis, on trouve:

  • Belleydoux
  • Bolandoz
  • Chaux des Prés
  • Frasne
  • Le Haut Saugeais Blanc – Hauterive La Fresse
  • La Malmaison
  • La Combe Saint Pierre
  • Le Lac des Rouges Truites
  • Les Combes Dernier
  • Les Crozets
  • Les Granges Dessus
  • Longchaumois
  • Le Meix Mussy
  • Menthières
  • Nods
  • Saint Laurent en Grandvaux
  • Val de Vennes

Je vous souhaite bien du plaisir à découvrir ces sites lorsque la neige seraen quantité suffisante !

New piste preset for iD

I made some modification in the ski piste presets for the iD editor. This is mainly intended to differentiate the meaning of piste:grooming and piste:difficulty tags depending on the type of piste(downhill, nordic, hike, etc …).

Descriptions are according to the wiki, which is rather stable for years.

Maybe some want to give it a try here to see if everything looks fine: iD master preview.

Comparison of Skimap.org and OpenStreetMap data

I have ask myself for some time now how I could have an estimation of the completeness of OpenStreetMap when it comes to ski pistes. I’m certain that with our more than 100’000 km ofpistes, downhill and cross-country combined, we are the biggest global skipistes database of this type, but what exactly remains to map? I needed something to compare to.

There is this great site called Skimap.org where contributors can upload scans and photos of ski maps from their favorite ski area. They have more than 3000 skiareas listed. These ski areas location are crowd-sourced by their contributors, and skimap.org offers an open API. So I can certainly find a way to compare this with OpenStreetMap data, no ? Yes, so I did. And many thanks to Russel for making Skimap.org !

The comparison goes both ways, first there is a long list called Pistes missing from OpenStreetMap.org.

Then we have a map showing Ski areasmissing in Skimaps.org.

It’s not perfect, because there are OSM ways on one side that are not really(or rarely) grouped as ‘ski resorts’ and single points on the other side. So of course in some case the distance threshold chosen (5km) is maybe not the best, and in some case Skimap.org ski area localization could be improved.

OpenStreetMap ‘ski areas’

No, they are not built-in in the OSM database. There is the tag ‘landuse=wintersports’ to tag ski resorts, but it is seldom used. The rejected relation proposal ‘site=piste’ attracts even less contributions.

So for this comparison they are build in a database like this :

The pistes from OSM are buffered by 500m, then glued in big polygons. Very big polygons (>30km) are split in equal size rectangular chunks ranging from 20km to 40km. This is a bit arbitrary but allows to more or less efficiently separate interconnected ski areas.

In the end, this gives >3500 downhill ski areas, and the same number ofnordic skiing areas.

What have I found ?

First a really good news : both projects contributors can still have alot of fun contributing for a while. Skimaps.org excels in the USA, and OpenStreetMap.org is better in Europe.

At first glance around 800 ski areas can be found in Skimap.org but not in OpenStreetMap. For Skimap.org, a lot of small and micro downhill resorts are missing (apparently > 1500). For nordic skiing, it’s really worse, but it’s not really the target audience I guess.

Also, OSM seems more complete when it comes to lifts (aerialways) than for ski pistes themselves. I would risk an explanation here. There is a lot of gondolas enthusiasts (https://www.remontees-mecaniques.net/, http://www.funivie.org/web/,Lift-World.info https://lift-world.info/, …), and I suspect people are mapping lifts systematically. Armchair mapping is also possible for aerialways on the contrary to ski pistes.

How does it helps ?

Both project’s data have open license, but not compatible (CC-BY-SA vsOdBL). So each can be used for the other as an inspiration, but not as a direct data source. Needless to say ski maps uploaded at Skimap.org are for the vast majority copyrighted and not to be used for mapping at OSM.

For Skimap.org contributors, they can use the map produced to spot a ski area in OSM, investigate on the web and find documentation of interest for the project. For OSM contributors, well, as usual : find a place with ski pistes to map, take a train ticket, your gear and GPS, and go !


Skimap.org also have some more information about its ski areas, for example if they are closed. This could be used to spot places in OSM where some map curating is needed. Also, I spotted on the maps some isolated pistes in OSM that looks strange. In short, some idea for ski-related QA in OSM.

Copyright notice

OpenStreetMap® is open data, licensed under the Open Data Commons OpenDatabase License (ODbL) by the OpenStreetMap Foundation (OSMF).

Skimap.org by https://skimap.org/ is licensed under a Creative CommonsAttribution-Noncommercial-Share Alike 3.0 United States License.

Ski pistes mapping 2018

It’s been a few years since the last statistics about ski pistes mapping in Openstreetmap.

You know it: Openstreetmap has the biggest worldwide skimap available. And still growing !

From today stats:

  • Crossountry trails: 67961 km
  • Alpine runs : 37287 km
  • Lifts: 17647 km
  • Sled runs : 1376 km

While at a slower pace than in the glory years, the length of the ski runsmapped in OSM grow every year with several thousand of kilometers. This means that there is still some ski pistes to map, and a good question is how many ? I’m trying to have some clue in comparing other available skiareas-related listings, such as Russel’s excellent Skimaps.org. I’ll keep you informed.

Edit : Ah, it’s more than 100’000 km of ski pistes without the lifts now !

2017 style improvements

I make no mystery of it: I’m a cross-country skier. I’ve run alpine skis only twice in my life, and definitely prefer the wild and quiet areas where you’re alone sweating your way in the middle of nowhere. This had had consequences on Opensnowmap.org, and I did not spent enough time on downhill runs rendering style. It was crowded and definitely not clear enough, but this is about to change. Now that the ski season is almost done, I’m rolling out a major style change.

Alpine runs

Downhill ski runs are now cleaner (I hope). Especially transition is smoother between pistes mapped as areas and those mapped as ways. At high zoom,pistes let a clear view on the contour lines and fade in better on the topo-style base map.


The less common pistes type (skitours, snowshoes, sled, and sleigh) are now rendered with icons. Curling, ice-stock and hockey icons have been added.

Pistes overlaps

Sometimes pistes can be used for several activities, now Opensnowmap is able to render piste tagged like piste:type = downhill;sled or other combination.

I hope this improved map will please you, and you are welcome to make any remarks or request improvement here.

External users

As long with the new style, the tiles URLs changes. As your website or appuses a proper referer, I am able to contact you with the new URL, of course. The URL is http(s)://tiles.opensnowmap.org/pistes/{z}/{x}/{y}.png.

For the offline users, please note that the monthly .mbt tile set from 28.04.2017 is the last one available with the old style.

Improved ski ressorts rendering

OpenSnowMap.org renders ski ressorts at zoom 10,11 & 12. For this, it takes either site=piste relations or landuse=winter_sports polygons, and checks what type of pistes they contain (downhill, nordic, sled,etc…) in order to display small icons next to the ressort name.

Until now, these icons where pre-calculated images of all possible combinations.They were not so nice, and did not scale well with the big tiles used on the mobile site.So I built a very handy font file, called Ski.ttf, that looks like this:

This allows me to use Mapnik list-placement on TextSymbolizers to position the needed icons nicely.

It will takes some time for the tiles to re-render, so here what it looks like:

before / after comparison