In order to promote a more sustainable mobility society, the French government initiated a few years ago a “Car free day” (In town without my car!). Since the year 2000 this initiative has become an overall European action. In the framework of this policy the city of Bordeaux has made the choice to ban the cars from its centre area every first Sunday of the month. Besides a decrease of the air pollution during this period, acoustic measurements show a big change in the noise environment. To verify this effect, we made a comparison between the audio recordings of the soundscape, of the first Sunday and the normal Sunday of the month. The “sound walk” followed a trajectory with different urban forms. It started on the Place des Quinconces (a very large square), passed the Place de la Comédie, followed the Cours de l’Intendance (a broad avenue), rue Vital Carles (a narrow street) and finished in front of the St André cathedral. We used for the recordings a “dummy” head with Digital Audio Tape recorder. In order to compare the different acoustical ambiances of the first Sunday and the normal ones, we analysed them on sound level.