A train control unit may comprise a probe attached to a first rail of a track way, and a sensor device attached to a second rail of the track way configured to determine the position of the probe, whereby the position of the first rail relative to the second rail may be determined. The train control unit is preferably independent of equipment controlling the position of the first and second rails. Some embodiments of the train control unit may be employed as a track monitor, a switch monitor and/or a wayside monitor.