Abstract: A system and a method for warning a person, steering a displaceable object, of an intrusion of the object into a section of a traffic route that is at least temporarily protected. The system includes an activatable device for determining the location of the displaceable object in relation to a threshold; a device for comparing the distance of the displaceable object from the threshold with a threshold value, to determine whether the threshold has been violated; and a transmitter and a receiver situated in the displaceable object. If the threshold is violated and simultaneously activated, the transmitter emits warning signals that are tuned to the receiver. The receiver of the displaceable object supports a plurality of predefined radio channels and the transmitter sends the warning signals on all the channels. The system further has a device situated in the object for acoustic and/or optical emission of the warning signals.