How do I open an OSM map?

I’ve just downloaded Italy from ‘’ and don’t know how to open it on Garmin Basecamp. Will someone please send me an idiot guide or give me a link to somewhere that explains the process?
Thank you!

Did you download the *.exe version ? If yes, execute it, that’s it.
I seem to remember that one needs at least two maps, so maybe install a 2nd one if that doesn’t work.

Thanks for your reply. No, I don’t think so.

I downloaded the file from, clicked on Italy, Garmin and the files that downloaded onto my PC say ‘Disc Image File’. Should I be doing something different?

Thanks again


This file is for a garmin gps device. For Mapsource and Basecamp use the download button named “Win”. When you hover over it it shows a file name
ending with *.exe.

I did as you said and I can now view it in Basecamp - thank you very much!

One more question; if I want to load the Italian map onto my Garmin Montana do I need to use the file I originally downloaded entitled ‘Garmin’?

Best regards


Yes, the Garmin device expects a so called gmapsupp.img in the folder Garmin. So, if you have an SD cart you have to create that folder
and copy the file into it. The Montana allows any name, just make sure that you keep the *.img extension.

Thanks again.