(Main article: First day on the Somme) The 19 mines on the first day of the Somme were mines of varying sizes dug by tunnelling companies of the Royal Engineers under the German lines on the Western Front during the First World War. The group consisted of eight large and eleven small charges which were 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 the mines on the first day of the Battle of the Somme ranks among the largest non-nuclear explosions.