Semaphore signals at Craven Arms station

Image: © Flying Stag Taken: 17 Jan 2011

The Marches Line is one of the remaining secondary routes in the UK still retaining this essentially Victorian technology. A northbound train is approaching from behind the camera and though it will stop at Craven Arms has the "all clear" to the next section indicated by three dropped signal arms. In the foreground is a "facing crossing", a track configuration always avoided if possible. It consists of two "points" or "switches", each of which offers a choice (controlled by the signalman) of two routes to an approaching train. In this particular location, southbound trains bound for the Heart of Wales Line must use this crossing to enter the northbound platform the 'wrong way' before diverging to the HoW branch. Facing points are potentially dangerous as there is a risk of one or more switch blades moving under a passing train causing a dangerous obstruction to both tracks. This risk does not arise with a "trailing" or converging switch as the train simply forces it way past the faulty switch. Facing points are therefore always protected with a complex mechanical system of slotted interlocking bars, attached not only to the point mechanism but also to any signal control wires which directly or indirectly control the point.

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