Hi Greg, there is no consistency in a way Garmin's devices display different objects. Even if you see something in BaseCamp it doesn't mean that this object will be visible on nuvi or outdoor device. There are some informations for meaning of objects (poi, lines, areas), which you can find on some web pages, for example: http://wiki.openstreetmap.org/wiki/OSM_Map_On_Garmin/POI_Types http://wiki.openstreetmap.org/wiki/OSM_Map_On_Garmin/Polyline_Types http://wiki.openstreetmap.org/wiki/Editing_OSM_Map_On_Garmin/Area_Types As a general rule I suggest to follow description in cGPSmapper manual: http://cgpsmapper.com/manual.htm Usually maps contain a TYP file, which define graphics for objects. This somehow unify map view for different devices. I think TYP allows for viewing some objects, that otherwise would be invisible. -- Best regards, Andrzej