Roxburgh Castle was a castle sited near Kelso, in the Borders region of Scotland.
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. In 1314 it was retaken by Sir James Douglas, but was later lost again. 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. Its ruins stand in the grounds of Floors Castle, the seat of the Duke of Roxburghe.
In 1545, during the Rough Wooing, the English 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.

Roxburgh Castle - Engraving by William Miller 1830
According to "The Borders," by Alistair Moffat, an author from Kelso who specialises in history, the ancient fort of Roxburgh Castle was the location of what is now known as Arthur's "Camelot." In his book "Arthur & the Lost Kingdoms", he provides detailed analysis of the Roman occupation of the area, the Celtic Kingdoms and the language behind place names of the Scottish Lowlands, together with the battles fought by Arthur, concluding that Roxburgh Castle was indeed Arthur's base.
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