Originally, I wrote this post for my blog: http://plepe.at/398
I love mapping for the OpenStreetMap project, it’s a very pleasing thing to do. I especially like to do it as vacation activity, because then I’m exploring new places anyway, but I also like to do it my home town.
Recently I’m concentrating on mapping artwork and memorials. Even in a well-mapped city like Vienna, Austria, there’s still plenty to do. For example, most social housing building complexes (Vienna is famous for it’s social housing) have some kind of artwork, e.g. some murals or statues in the gardens.
I think, having a map feature in OpenStreetMap is not enough though. I want to add pictures and meta data (who made the object, when was it created, …). This is done in cooperation with the Wikimedia Foundation. In this article, I want to explain how I map these objects.
Often these objects already have photos on Wikimedia Commons. If not, I upload one or a few photos (whatever is reasonable). If there are several photos of the picture (or the object seems important enough), I create a category for the object (if it does not exist yet). Of course, the category should have the relevant categories for the location, the motive, the artist, etc.
Next, each object should have its own Wikidata entry. Haven’t heard of Wikidata yet? It’s a sister project to Wikipedia and Wikimedia Commons. As Wikimedia Commons is the platform for media (which is linked by Wikipedia), Wikidata is a platform for semantic and linked data. E.g. an entry for a city would have values for the population size at specific historic dates, links to the wikidata entry of current and former mayors, link to other data sources (Encyclopedia Brittanica, Library of Congress), link to its Wikimedia Commons category, and so on (e.g. Vienna). Most infoboxes in Wikipedia are now automatically created from Wikidata data.
So, each object should have its own Wikidata entry. Of course, you should check if a Wikidata entry already exists – if yes, check if the data is complete. It should have values for (if available):
When done, edit the Wikimedia Commons category, and add the following line, so that the category gets a nice infobox on the side (the wikidata entry needs an entry “commons” in the multilingual sites with the Category name to work):
Finally, the map feature in OpenStreetMap. This can be a node or an area. If the object is located on the wall of a building I make the node a part of the building contour. The entry should have the following tags:
Further tags like wikipedia=](https://wiki.openstreetmap.org/wiki/Key:wikipedia), [image=, wikimedia_commons=* are not necessary, as this information can be read from the Wikidata entry. I do not remove these tags though, if I find them.
Often, map features already have a wikidata/wikipedia-tag which points to the person which it memorizes. This is wrong, because this should be a „subject:wikidata“ resp. „subject:wikipedia“ tag. Please change this.
How can you test your entries? There’s a list of tools which let you explore wikidata tags. I recommend OpenStreetBrowser, which is an application for OpenStreetMap data written by myself. It will show images of the map features and excerpts of Wikipedia articles.
Here are some examples of such features:
Comment from Polyglot on 3 August 2020 at 13:47
That’s a great explanation! Thank you for that tutorial.
Comment from Alan Bragg on 3 August 2020 at 14:46
You’ve inspired me to give it a try. Thank you.
Comment from coolmule0 on 8 August 2020 at 18:07
Really like this. Great guide, and nice to discover a neat way of browsing OSM through OpenStreetBrowser
Comment from Pieter Vander Vennet on 9 August 2020 at 11:22
I have a small editor for artworks here, which shows wikimedia-images: https://pietervdvn.github.io/MapComplete/artworks.html?z=16&lat=48.208&lon=16.371
Comment from martingggg on 10 August 2020 at 03:25
Very interesting your work.
I’ll make a note of your tag set to extend GLAM
See the OSM GLAM project born in Argentina (in Spanish)