Welcome and thanks for your interest in Road Trip. This web application is the result of a sub-project which is part of the more global one called GMapify. Feel free to explore this website full of maps and geodata. Maybe you could find other interesting stuff ;)
It gives you all level-1 (US states, french regions, ...) and level-2 (US counties, french departements) administrative areas you pass through when driving from one point to another. Polylines are currently available only for the US and France but nothing prevents you from choosing a start and/or an end address in countries where driving directions are available (like european countries). You will get the list of administrative areas in the sidebar anyway :)
#How it works?
Driving directions are given by Google. After that a reverse-geocoding is done using Geonames API to get administrative areas. Then states and counties are displayed. Altitude profile is provided by Topocoding and drawn thanks to Google Chart.