On the land side of El Morro, the high walls were encircled by a wide ditch. This design was expected to slow an approaching enemy while soldiers fired upon them from the crenels in the elevated battlements. This plan failed during the Battle of Havana in 1762. The British, after relentless bombarding the stronghold with artillery, exploded the ditch with a mine. When it filled with debris, the British troops easily crossed the moat and captured El Morro.