Hi Markus, the Garmin img format doesn't allow such a resolution. It uses only 24 bits to store the lat / lon values, that means 40000km / 2^24 which gives ~ 2.4m on the equator. Think of a "bed of nails" with one nail every 2.4 meter and try to draw lines by connecting these nails. Gerd ________________________________________ Von: mkgmap-dev <mkgmap-dev-bounces@lists.mkgmap.org.uk> im Auftrag von Markus P. <markus_brd@gmx.at> Gesendet: Mittwoch, 13. April 2016 02:27 An: mkgmap-dev@lists.mkgmap.org.uk Betreff: [mkgmap-dev] Garmin Contour Lines Hi Is it in general possible to convert high detailed Height- Lines to a garmin Map ? High Detailed means Lines with 1m distance in height. I tried but my Lines look useless because they look cross-connected So how to generate such contour lines ? glg Markus _______________________________________________ mkgmap-dev mailing list mkgmap-dev@lists.mkgmap.org.uk http://www.mkgmap.org.uk/mailman/listinfo/mkgmap-dev