Abstract: A wireless train proximity alert system provides a constant warning signal to warn vehicles approaching a train crossing when a train is also approaching the crossing. The system includes a transceiver, positioned on the train itself or at the side of the track, for transmitting a train proximity signal, which preferably includes the train's speed and position. A crossing-based transceiver receives the train's proximity signal and transmits the boundary coordinates of a warning zone when the train's estimated time-to-arrival at the crossing is within a predetermined range. A vehicle-based receiver receives the warning zone signal and the crossing's position, compares them to the vehicle's position and speed, and produces an alarm to the vehicle's operator when a potential accident is indicated.