I tracked myself using the iphone application GPS Kit Free, which along with the map, sped and altitude diagram, also stores the data in a kml and a gpx files. Based on the data, I wanted to show the corrolation between the altitude (which could suggest the nature of transportation; underground being for the metro), and the speed. I used the OSM data to reproduce the area of Barcelona that appeared on my tracking maps. I gave a thickness to the tracks lines so they could be readable in plan as well as in top view.