Lochnagar Mine Crater

On the morning of 1 July 1916, the British army detonated a mine in the village of La Boisselle, just north of Albert in France. The Royal Engineers had dug a tunnel, 50 feet deep, extending for about 300 yards from the British lines to the German front line. There, under a German position called 'Schwaben Hohe,' they laid a mine consisting of over 25 tons of Ammonal.
The resulting explosion blew almost half a million tons of chalk into the surrounding fields, sending debris over 4,000 feet into the air. It created a vast hole 300 feet across and 90 feet deep. Known as the Lochnagar crater, it remains the largest crater made in warfare to this day.