For centuries, the quiet, rural area around the tiny hamlets of Eastriggs and Gretna lay undisturbed with only a few farms and small settlements dotted about. Then in 1915, soon after the start of World War One, the men from the Ministry of Munitions arrived and everything changed.

By 1917 the factory was producing 1,100 tons of cordite per week, more than all the other munitions plants in Britain combined, providing much-needed ammunition or the troops fighting on the front line.

Within a period of 12 months the government had taken over the farms and in their place was one of the most remarkable factories on Earth.

Stretching for nine miles, HM Factory Gretna employed 30,000 workers, at its height, to manufacture RDB Cordite, a new type of munitions propellant.