New server is being deployed – URL change

Dear users, A generous donation accelerated the deployment of OpenSnowMap.org on a more powerful server. No big changes, except a faster rendering and the possibility to serve more tiles. This will help in following the increasing number of requests for ski maps.

Many thanks to the team at snow-forecast.com !

Part of the map requests are already handled by this new server, so you may experience a longer load time while the tile cache is building up.

If you are using the ski map tiles on your own website, please use the url http://tiles.opensnowmap.org/pistes/z/x/y.png, tile servingfrom http://www.opensnowmap.org/pistes/z/x/y.png will soon be deprecated. Also, heavy users (> 50’000 tiles per day) are requested to access the tiles via their own cache.

Keep an eye on map changes

Some of you may already use the daily and weekly change view of Opensnowmap.org to check for changes on the ski pistes they mapped.
Today, this view have been improved and now gives more information about the actual change. Is this a way, a relation deleted, a simple node moved? A new processing associated with a detailed legend will help to better understand thechanges and maybe spot errors.

See, yesterday apparently someone seems to have refined a nicely mapped skating ring.

This view coupled with the  button will allow you to find more information about the modified element. It is still a bit frustrating not to be able to check on deleted elements, I will try to add daily and weekly .html change list to allow this.

In practice, each night, the pistes of the OpenStreetMap database at 00:00GMT are compared to the pistes that were there the day and the week before. Geometries are simplified in order not to display to much information.

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 !

More

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.