On July 1, 1916, 30 tons of explosives left as a trap by British soliders exploded, starting the Battle of Somme in France. The explosion was said to be heard 200 miles away in London, and it left a crater nearly 400 feet wide. In 1978, a London man, Richard Dunning, bought the land around the crater to preserve it for history. On July 1, 2016, people gathered to honor the 100th anniversary of the start of the battle, which took the lives of 131,000 British troops.