Mines on the first day of the Somme

On the morning of 1 July 1916, a series of 19 mines of varying sizes were blown to start the Battle of the Somme. The explosions constituted what was the loudest human-made sound in history, and could be heard in London. The largest single charge was the Lochnagar mine south of La Boisselle with 60,000 lb (27 t) of ammonal explosive. The mine created a crater 300 ft (90 m) across and 90 ft (30 m) deep, with a lip 15 ft (5 m) high. The crater is known as Lochnagar Crater after the trench from where the main tunnel was started.

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