Mines on the first day of the Somme

The 19 mines on the first day of the Somme comprised a series of underground explosive charges, secretly planted by British tunnelling units beneath the German front lines on the Western Front during the First World War, ready to be detonated in the morning of Saturday 1 July 1916, the first day of the Battle of the Somme (1 July – 18 November 1916). The joint explosion of these mines ranks among the largest artificial non-nuclear explosions.

The tunnelling companies of the Royal Engineers were to make two major contributions to the opening attack of the Battle of the Somme: Firstly, by preparing a number of large and small mines; and secondly, by preparing a series of shallow Russian saps from the British front line into no man's land, which would be opened at and allow the infantry to attack the German positions from a comparatively short distance.

The 19 mines consisted of eight large and eleven small charges deep in the chalky ground which were "overcharged" to throw up high lips for screening and to give advantage to the attackers when (or if) they captured the resulting craters. The mines can be grouped into the large mine at Beaumont-Hamel (beneath Hawthorn Ridge Redoubt), the charges near La Boisselle (consisting of the large Lochnagar and Y Sap mines as well as the smaller Glory Hole charges), the three large Triple Tambour mines opposite Fricourt, the Bulgar Point and Kasino Point mines, and the nine small charges placed further south. The small charges were to remove local German positions like machine gun posts and were laid from the ends of comparatively shallow tunnels.

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