Bristol is a city, unitary authority area and ceremonial county in South West England, 105 miles (169 km) west of London, and 44 miles (71 km) east of Cardiff. With an estimated population of 416,400 for the unitary authority in mid-2007, and a surrounding urban area with an estimated 561,500 residents, it is England's sixth, and the United Kingdom's eighth most populous city, one of the group of English Core Cities and the most populous city in South West England. It received a Royal Charter in 1155 and was granted County status in 1373. From the 13th century, for half a millennium, it ranked amongst the top three English cities after London, alongside York and Norwich, until the rapid rise of Liverpool, Birmingham and Manchester during the Industrial Revolution in the latter part of the 18th century. It borders the counties of Somerset and Gloucestershire, also located near the historic cities of Bath to the south east and Gloucester to the north. The city is built around the River Avon, and it also has a short coastline on the estuary of the River Severn where it flows into the Bristol Channel. Bristol is the largest centre of culture, employment and education in the region. Its prosperity has been linked with the sea since its earliest days. The commercial Port of Bristol was originally in the city centre before being moved to the Severn Estuary at Avonmouth; Royal Portbury Dock is on the western edge of the city boundary. In more recent years the economy has depended on the aerospace industry, and the city centre docks have been regenerated as a centre of heritage and culture. There are 34 other populated places on Earth named Bristol, most in the United States, but also in Peru, Canada, Jamaica and Costa Rica, all presumably commemorating the original.