Garmin maps segment/tile numbering (

Dear all,

as I am quite new to OSM, first I would like to thank all the people who make the OSM maps and everything related to them possible.
I started to contribute by updating my neighbourhood in OSM.

Planning a bike trip across Europe this summer I downloaded the predefined country versions of several maps from
Installation and use in Mapsource is fine and I created a custom TYP for better looks on my 60CSx.

The problem I have is that the segment numbers of the tiles are reused in different maps (i.e. OSM Generic Routable (63420949)).
This creates a problem as Mapsource will only recognize the first selected (i.e. from NL) and will ignore others with the same name/number when creating a map set.

I couldn’t find a quick fix to change the tile numbers.

Would it be possible to have unique tile numbers and perhaps even map related names (i.e. OSM NL Routable) for the predefined country maps?

Please forgive me if I have missed something :wink:

Kind regrads,

btw, JaVaWa is also complaining about the numbers reused in different maps, but can’t fix it …

You can try my Openfietsmap Europe, it is a little out of date, have to upload a new version sooner or later.

Or else, you can assemble a new map with mkgmap and all the tiles you need. I have a windows batch script for this:

Thank you for the tip Ligfietser.

Unfortunately all the downloadlinks on the page return an error 500 at the moment.
Let’s hope for Google to fix it …


Yes, I see that this error page pops up only if you are not logged in (normally you dont have to), maybe Google changed their policy and only users can download stuff or maybe its a bug?

Seems Google fixed the download error now

Sorry for resurecting this thread.

I’ve come across the same error, but I need some clarification here…

Am I right in assuming that as long as the tiles with identical numbers are in fact identical, this won’t have an effect?

I create an OSM map for my Garmin containing all of Germany, and one of France. There will be some overlaping tiles and JaVaWa will complain about duplicate segment numbers. But as it doesn’t matter for me from which map the specific segment is taken - they are duplicates of each other - it will still work fine?

I would appreciate any answers on this.


Some Garmin devices will have problems with duplicate segments, some won’t. General rule is: always avoid duplicate maps, map segments and/or segment numbers.
If you don’t, you may experience problems with map display and routing.

Any particular information on the eTrex 20 in this regard?

If I didn’t have to care about this error, it would make managing - and in the future updating as well - the maps much simpler…
I’ll see if I notice anything weird.
=> How / what should I notice if it did affect my device?


I don’t know how the eTrex behaves on this aspect. Duplicate map segments can cause trouble with routing. I have seen several reports where users encountered problems when following a route; to find out if it affects your device it would require a field test…


I’m not using the eTrex for “turn-by-turn” routing, but plan on using it as a small, additional backup when flying and for saving tracks.
But I’ll keep my eyes open for any issues and if I do encounter any, I know where to start troubleshooting.

For now I’m happy to have most of Europe and the whole of Africa on a single 32GB mSD card and not having to shift files back and forth, the eTrex is a great improvement on the Vista HCx that I had a few years back…

Thanks a lot for your help and your quick answers!


edit: one more question

The “number of tiles” limit. Is there an easy way to see how many tiles a map contains? Is it the same as the number of segments?

segments, tiles: different name for the same things. So, the answer is yes.
Note that the tile limit applies to the sum of the tiles on the device itself and those on the SD card. The tile limit does not apply to BirdsEye maps/imagery.