Abstract: A warning device for indicating a position of a golf cart on a golf course with respect to a restricted area includes a transmitter of an energy wave and a receiver of the energy wave. In one embodiment, the receiver is mounted on the golf cart and the transmitter is located at the restricted area. In another embodiment, both the transmitter and receiver are mounted on the golf cart and a reflector for the energy wave is mounted at the restricted area. The energy wave contains information about the position of the golf cart with respect to the restricted area such that an indication of the position can be generated by lighting a lamp, or by generating a sound, or by generating a digital visual display.