Bewcastle is a large civil parish in the City of Carlisle district of Cumbria, England.
According to the 2001 census the parish had a population of 411. The parish is large and includes the settlements of Roadhead, Shopford, Blackpool Gate, Roughsike and The Flatt. To the north the parish extends to the border with Scotland. As well as Bewcastle Castle this border area includes Askerton Castle. St Cuthbert's churchyard contains the famous 7th Century Bewcastle Cross. The sundial on its surface is the oldest in Britain, divided into the four 'tides' which governed the working day in medieval times. Its importance has been described by Nikolaus Pevsner thus; "The crosses of Bewcastle and Ruthwell....are the greatest achievement of their date in the whole of Europe." A perfect copy of the whole cross is located in the churchyard of St Mary's neo-Romanesque Church at Wreay near Carlisle.
Bewcastle is also known for its unusual hexagonal Roman fort, which has been identified as Fanum Cocidi.
The origin of the name Bewcastle can be traced accurately from its spelling in ancient documents. These show that it was originally "bothy/booth caster", which translates as "the roman fort where there were bothies or shielings". Antiquarians, who did not have our access to well-catalogued and studied ancient documents, leapt at the chance to link the place name with a semi-mythological figure named Bueth, due to his romantic links with the prestigious Barony of Gilsland. Unfortunately, Bewcastle is outside the Barony, and the well-respected book "Place-names of Cumberland" states that it is impossible for Bewcastle to be named after Bueth.
Two brothers born in Bewcastle, Joseph Armstrong (1816–1877) and George Armstrong (1822–1901), became steam locomotive engineers; their careers were spent mainly on the Great Western Railway.