Devon (/ˈdɛvən/ DEV-ən, historically known as Devonshire /ˈdɛvənʃɪər, -ʃər/ DEV-ən-sheer, -shər) is a ceremonial and non-metropolitan county in South West England. The most populous settlement in Devon is the city of Plymouth, followed by Devon's county town, the city of Exeter. Devon is a coastal county with cliffs and sandy beaches. Home to the largest open space in southern England, Dartmoor (954 km2 (368 square miles)), the county is predominately rural and has a relatively low population density for an English county. The economy of Devon is heavily based on tourism and agriculture.