Roxburgh Castle was a castle overlooking the junction of the rivers Tweed and Teviot, in the Borders region of Scotland. It took its name from the royal burgh of Roxburgh, which the Scots destroyed along with the castle after capturing it in 1460. Today the ruins stand in the grounds of Floors Castle, the seat of the Duke of Roxburghe, across the river from Kelso.
The castle was founded by King David I. In 1174 it was surrendered to England after the capture of William I at Alnwick, and was often in English hands thereafter. The Scots made many attempts to regain the fortress. On 19 February 1314 it was retaken by Sir James Douglas (the "Black Douglas") by disguising his men as cows, but was later lost again. The castle was Edward III of England's base of operations during his 1334 winter campaign against the Scots. Henry V of England made repairs to the castle after a Scottish siege in 1417. In 1460 James II was killed whilst bombarding the castle, when one of his own cannons exploded. However Roxburgh was stormed, and James' queen Mary of Guelders had the castle demolished.
In 1545, during the Rough Wooing, the English garrison commanded by Ralph Bulmer built a rectangular fort on the site at the instigation of the Earl of Hertford. This was destroyed in 1550 by the terms of the Treaty of Boulogne.
In his books The Borders and Arthur & the Lost Kingdoms, Alistair Moffat argues that an ancient fort on the site of Roxburgh Castle was Camelot. The 1314 capture of the castle is one of the inspirations of "The Three Perils of Man" by James Hogg.
- Coventry, Martin (2006). The Castles of Scotland. Birlinn. ISBN 1-84158-449-5.
- Mike Salter (1985). Discovering Scottish Castles. Shire Publications Ltd. pp. 17–18. ISBN 0-85263-749-7.