Abstract: Device prohibiting access of alien vehicles to given zones, while allowing recognized, identified and authorized vehicles to enter, consisting of at least one re-usable modular element with instantaneous positioning which requires no specific installation, comprising an access-control barrier (13) activated by the help of the lever (14) of a release mechanism (9) (11) (17) (18), operable by a lever (11) and by a stop-barrier (2), which is released by the action of a skid (16) on a skid (9) pushing a bolt (7), the whole being incorporated in a frame (1).