Dartmoor Training Area has been used regularly for military training since 1873, although it was used earlier during the Napoleonic and Crimean Wars. In 1906-07, seven miles of roads were built on the north moor to facilitate the movement of guns. There are three established firing ranges at Okehampton, Willsworthy and Merrivale. The area taken up with live firing ranges is 9,187 hectares (22,664 acres) and they are used on average 120 days each year. They are used for small arms, mortars and artillery smoke and illuminating shells.