Newport is a cathedral and university city and unitary authority area in south east Wales. It is located on the River Usk close to its confluence with the Severn Estuary, approximately 12 miles northeast of Cardiff. At the 2011 census it is the third largest city in Wales, with a city population of 145,700 and an urban population of 306,844. The city forms part of the Cardiff-Newport metropolitan area with a population of 1,097,000. Newport has been a port since medieval times, when the first Newport Castle was built by the Normans. The town outgrew the earlier Roman town of Caerleon, immediately upstream, and gained its first charter in 1314. It grew significantly in the 19th century, when its port became the focus of coal exports from the eastern valleys of South Wales. Until the rise of Cardiff from the 1850s, Newport was Wales' largest coal-exporting port.