Cornwall (/ˈkɔːrnwɔːl/ or /ˈkɔːrnwəl/; Cornish: Kernow, [ˈkɛɹnɔʊ]) is a ceremonial county and unitary authority area of England within the United Kingdom. It is bordered to the north and west by the Celtic Sea, to the south by the English Channel, and to the east by the county of Devon, over the River Tamar. Cornwall has a population of 536,000 and covers an area of 3,563 km2 (1,376 sq mi). The administrative centre, and only city in Cornwall, is Truro, although the town of Falmouth has the largest population for a civil parish and the conurbation of Camborne, Pool and Redruth has the highest total population.