Swansea, officially known as the City and County of Swansea, is a coastal city and county in Wales. It is Wales's second largest city and the UK's twenty-sixth largest city. Swansea lies within the historic county boundaries of Glamorgan. Situated on the sandy South West Wales coast, the county area includes the Gower Peninsula and the Lliw uplands. The City and County of Swansea had a population of 239,000 in 2011, making it the second most populous local authority area in Wales after Cardiff. During its 19th-century industrial heyday, Swansea was a key centre of the copper industry, earning the nickname 'Copperopolis'.HistoryArchaeological finds are mostly confined to the Gower Peninsula, and include items from the Stone Age, Bronze Age, and Iron Age. The Romans reached the area, as did the Vikings.Swansea is thought to have developed as a Viking trading post. Its name may be derived from Sveinn's island (Old Norse: Sveinsey) – the reference to an island may refer to a bank at the mouth of the river Tawe, or an area of raised ground in marshes. An alternative explanation is that the name derives from the Norse name 'Sweyn' and 'ey', which can mean inlet. The name is pronounced Swans-y ), not Swan-sea. The Welsh name first appears in Welsh poems at the beginning of the 13th century, as "Aber Tawy".