Mines on the first day of the Somme

On the morning of 1 July 1916, the first day of the Battle of the Somme during World War I, underground explosive charges planted by British tunnelling units were detonated beneath the German front lines. The joint explosion of these mines ranks among the largest artificial non-nuclear explosions.

Eight big and eleven tiny charges were buried deep in the chalky earth to make up the 19 mines. They were "overcharged" to throw up high lips for screening and to give advantage to the attackers if they were able to capture the resulting craters.^[1] The larger mines were located near Beaumont-Hamel beneath Hawthorn Ridge Redoubt and near La Boisselle (Lochnagar, Y Sap, and Glory Hole charges), Fricourt (Triple Tambour mines), Bulgar Point and Kasino Point. The smaller charges for removing German positions, such as machine gun posts, were laid from the ends of comparatively shallow tunnels.

In addition to the mines, the British tunnelling units also prepared a series of shallow saps extending from the British positions into the no man's land. They allowed the infantry to attack the Germans from a comparatively short distance once the battle commenced.^[1]

When they were fired, the Lochnagar and Hawthorn Ridge mines were the largest ever detonated, and reports suggest that their sound could be heard in London and beyond. The mine detonations on the first day of the Somme were surpassed by those fired at the start of the Battle of Messines the following year.