Hi, I have been experimenting with mkgmap for a couple of months now. I am not really a Java programmer, but I can read and understand the code easily. Having been surprised by how certain map attributes come through on the Garmin using the standard stylesheets, I have been looking into how the chain currently works from OSM data to mkgmap to the style sheets to the Garmin device so I could consider adjusting the way things are tagged in order to improve the end result. I am of course not advocating "tagging incorrectly for the renderer". My intention is to optimise routing instructions, including both actual turns and the spoken instructions. Browsing through the code, I have discovered quite a few pieces of logic which refer to specific OSM tags which are not, or poorly, documented. For example, the "through_route" relation is extremely useful, and I have seen that the "display_name" tag can override "ref" and "name". Neither of these are documented on the OSM wiki. There are also quite a few "internal" tags in the mkgmap namespace which could concievably be set in the OSM data to override default algorithms in the code. Now there's a discussion taking place about revising the documentation for the command line options, would it be an idea to start some documentation of the way tags are used within the Java code? This would assist anyone wanting to tweak the style sheets without diving into the code. Colin