This is an N-scale Model Railway I built containing many electromagnetic relays to switch track circuits and signals. It has 20 multicoloured automatic signals controlled by track circuits, there is also an on-board micro computer which has access to all the signals, points and track circuits. The design is based of the London Underground District Line with cables strung at the side of the track. Unlike most model railways, these wires actually control the railway. There is a video showing it in operation on YouTube.