The Otterburn Army Training Estate (ATE) was established in 1911 and covers about 242 square kilometres (93 square miles) of the Southern Cheviots. It is owned by the Ministry of Defence (MoD), and used for training some 30,000 soldiers a year. Otterburn is the UK's largest firing range, and is in frequent use — artillery can be clearly heard from Lindisfarne to the north-east and Fontburn Reservoir in the south.