Map showing travel times by road in France from Paris. Each color shows all the places whose travel time from Paris is between H and H + half an hour. For instance, the first ring circling Paris contains places where you can go from Paris in less than 30 minutes ; the second one, in 30 to 60 minutes ; the third one, in 1 hour to 1 hour and a half ; etc. 
Travel times were calculated through Google Maps, from the Place de l'Hôtel de Ville in downtown Paris to the center of each town or city shown by a dot. Big dots are for prefectures ; small ones, for other cities or towns. Other travel times than those for cities shown on the map were calculated to be able to make the map more precise. Data is for early December, 2008.
Own work ; from Bayo's File:Départements de France.svg
Benjism89 ; bayo