How do I combine Wikipedia Commons maps into one display?

Question

I am currently working on a project where I am looking to map out a set of state routes. After picking x amount, I want to construct one aggregate map of those routes so that I can visualize them together. I see that on the Wikipedia page for US Interstate Routes, it's possible to do this: https://en.wikipedia.org/wiki/Interstate_Highway_System#/map/0.

Each of the individual red lines on the map links to a data source in Wikimedia Commons, for example "Data:Interstate 70.map": https://commons.wikimedia.org/wiki/Data:Interstate_70.map. So, I can search up all of these individual routes, but I'd like to be able to find them all and combine them into one (zoom-able) image...

Additionally, if the route doesn't already exist as a data source in Wikimedia: I've noticed that existing routes are sourced from OpenStreetMaps. I've tried messing around with the site a little, and I'm not sure how Wikimedia Commons contributors are constructing the route (as a whole -- I can select small segments just fine) in the first place and exporting/uploading it to Wikimedia Commons. For example, PA Route 50 shows up on the map in OpenStreetMaps, but I am unable to select it as a whole.

If there is a better service to do this with, that also works! I just want to visualize the routes together, and I don't care how it's done (other than manually taking screenshots and editing the photos together)

Any help would be appreciated! Thank you!

Answer 1

Wikipedia has it's own special way organising geo-data for these maps embedded in articles. Let's have a poke around...

If you mouse over the bottom credits of your map link, you can see reference to lots of different .map files. Likewise if you view the wikitext source on this article.

Here is the full list of referenced .map file names (one for each interstate):

Interstate 4.map
Interstate 5.map
Interstate 8.map
Interstate 10.map
Interstate 11.map
Interstate 12.map
Interstate 14.map
Interstate 15.map
Interstate 16.map
Interstate 17.map
Interstate 19.map
Interstate 20.map
Interstate 22.map
Interstate 24.map
Interstate 25.map
Interstate 26.map
Interstate 27.map
Interstate 29.map
Interstate 30.map
Interstate 35.map
Interstate 37.map
Interstate 39.map
Interstate 40.map
Interstate 41.map
Interstate 43.map
Interstate 44.map
Interstate 45.map
Interstate 49 1.map
Interstate 55.map
Interstate 57.map
Interstate 59.map
Interstate 64.map
Interstate 65.map
Interstate 66.map
Interstate 68.map
Interstate 69.map
Interstate 70.map
Interstate 71.map
Interstate 72.map
Interstate 73.map
Interstate 74.map
Interstate 75.map
Interstate 76 (Ohio–New Jersey).map
Interstate 76 (Colorado–Nebraska).map
Interstate 77.map
Interstate 78.map
Interstate 79.map
Interstate 80.map
Interstate 81.map
Interstate 82.map
Interstate 83.map
Interstate 84 (Oregon–Utah).map
Interstate 84 (Pennsylvania–Massachusetts).map
Interstate 85.map
Interstate 86 (Idaho).map
Interstate 86 (Pennsylvania–New York).map
Interstate 87 (North Carolina).map
Interstate 87 (New York).map
Interstate 88 (Illinois).map
Interstate 88 (New York).map
Interstate 89.map
Interstate 90.map
Interstate 91.map
Interstate 93.map
Interstate 94.map
Interstate 95.map
Interstate 96.map
Interstate 97.map
Interstate 99.map
Interstate 35W (Texas).map
Interstate 35W (Minnesota).map

Each of these is a file name of a .map file which you can download from wikimedia commons with a URL such as:

https://commons.wikimedia.org/wiki/Data:Interstate%204.map?action=raw

This gives you a json file. If you strip off the outer element containing meta data fields and take only the data field contents... that's valid geojson (Maybe there's a way to request geojson from wikimedia commons more directly)

So you could download all of those and set up that data (manually. Or did you want code to do that automatically?) and then I suppose you are left with a question a bit like this one: How to present a geojson file on a map.