Newbie: trying to use OSM with Garmin

In my innocence I thought this would be easy … :slight_smile: After 2 hours I am stuck.

  1. I downloaded UK maps from in OSM format (11GB)

  2. I downloaded mkgmap from I don’t recall where.

  3. I tried creating a Garmin map by using the command line

    java -jar mkgmap.jar --input-file=british-isles-latest.osm.osm.osm --gmapsupp
  4. I get as output a 4KB file which I suspect is not big enough …

I’m clearly going down the wrong path. Can someone please put me right, please?

Would a ready-made map from Free Routable Garmin Maps satisfy your needs?

For more ready-made options check the tables on OSM Map On Garmin/Download.

I also recommend to start with a ready made map linked by RetiredInNH.

If you want to create your individual maps with mkgmap please read first. The most important steps are explained there and will enable you to create your first map with mkgmap.

Thanks for this.

I downloaded the map I wanted (UK) and copied it across to the Garmin. The file I used was gmapsupp.img . When I start up the Garmin now it puts up come copyright signs, including for openmap, but I still have the old maps (I’ve checked what I can see on the satnav against the online Openmap.)

I must be missing something - renaming, downloading other files, … ???

I’d be grateful for your help. :slight_smile:

What model Garmin are you using? Did it have any maps installed previously?
You might need to go to the “Map Setup” menu, and enable the OSM maps, and disable any other maps.

It’s a 5 year old Garmin Nuvi. It previously had UK, Europe and USA maps installed.

After quite a bit of searching I found where I could enable OSM maps and disable others and now all is OK.