Differences between OSM and IMG

search for in www.openstreetmap.org at the “Rosenhofer Teich” and you will find two of them (two lakes, a small and larger one).

But if I load the IMG file for Austria from garmin.openstreetmap.nl I have only one such lake (the smaller one is missing).

What is the the reason for the difference?


Just an update:

All I see on my Gamrin Device is a small dot and the text “Rosenhofer Teich”. So I guess something is wrong with the tagging but I cannot see what,


If you post a permalink to the location on OSM, we can have a look and see what’s wrong with the tagging.

Here it is:


The larger one (norzh-west) is visible on my garmin. the smaller one (south-east) ist not visible.


The smaller lake has to be an inner member of the forest-multipolygon. I changed this already.

This is very logical, because if there is a lake, there can not be forest. :wink:

thanks for the help.

As an occasional user it’s the first time that I hear about the “inner member” (but this makes sense). I always thougt that if something looks good in the web browser thenit would look fine on a Garmin, too. What a mistake!


The mkgmap multipolygon code is very strict, so if things aren’t tagged correctly it usually won’t render correctly. The mapnik multipolygon code is much more generous, allowing for mistakes much more readily. The good thing about the mkgmap approach is that it generates error messages which you can then use to fix the OSM data.