A virtual-barrier system that defines a keep-out-zone for vehicles to avoid includes a transmitter, a location-detector, and a controller. The transmitter is configured to broadcast information regarding a keep-out-zone. The location-detector is configured to indicate a location of the transmitter. The controller is in communication with the transmitter and the location-detector. The controller is configured to determine boundaries of the keep-out-zone in accordance with the location, and operate the transmitter to broadcast coordinates of the boundaries of the keep-out-zone.