War Department Light Railways

The War Department Light Railways were a system of narrow gauge trench railways run by the British War Department in World War I. Light railways made an important contribution to the Allied war effort in the First World War, and were used for the supply of ammunition and stores, the transport of troops and the evacuation of the wounded.

Different track gauges were used in different parts of the world including 600mm, 760 mm (2 ft 5 ¹⁵⁄₁₆ in), 1,000 mm (3 ft 3 ³⁄₈ in) metre gauge and 1,050 mm (3 ft 5 ¹¹⁄₃₂ in).

The military light railways in France were of 600 mm (1 ft 11 ⁵⁄₈ in) gauge and used a variety of steam and petrol locomotives from French, British and American builders. The Germans installed their 600 mm (1 ft 11 ⁵⁄₈ in) gauge Feldbahn system early in the war. Trench railways of the World War I western front produced the greatest concentration of minimum-gauge railway locomotives observed to date.

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