Gunpowder production began here in the mid-17th century. Factory buildings were spaced far apart to stop an explosion in one building igniting an explosion in another. For 200 years, canal boats were used to transport materials such as coal, sulphur, charcoal and saltpetre between the factory buildings.

In 1856 the first wooden tramways and wagons were introduced. The site expanded to accommodate the manufacture of new explosives and propellants (such as cordite). As the site continued to grow, the tramways were replaced with first a 2 foot 3 inch, and later an 18 inch gauge railway. 

To avoid sparking an explosion, railway wagons were fitted with spark-resistant phosphor bronze wheels. All rolling stock was pushed by hand until the outbreak of the First World War. The war created a huge rise in the demand for explosives. In response, petrol/paraffin and battery powered locomotives were introduced to increase production. 

The site stopped manufacturing explosives and propellants during the Second World War; the railway fell out of use and was gradually dismantled. The site then became a top-secret Explosives Research and Development Establishment (ERDE). The Gunpowder Railway follows the route of the perimeter patrol path used by the ERDE.

The Gunpowder Railway runs a 2 foot 6 inch gauge, an unusual gauge historically favoured by the Ministry of Defence. Naval mine wagons have been converted into passenger carriages; the wagons were previously used to load mines onto the naval vessels at the Royal Navy Armaments Depot Trecwn, near Fishguard, Wales.

Image above shows women workers posing with a petrol/paraffin Ruston Procter locomotive. During the First World War, women made up half of the workforce at the Royal Gunpowder Mills. 1916

Banner image shows a Ruston Procter locomotive pulling trays of cordite to/from the drying stove. 1917