 The fortress never recovered from the sieges of these campaigns, and by the 16th century the Warden of the Scottish Marches described it as having fallen into "wonderfull great decaye".As the Scottish border became more stable, the military utility of the castle steadily diminished, and King James I finally sold the property off into private ownership in 1604.The Grey family owned it for several centuries; increasingly ruinous, it became a popular subject for artists, including Thomas Girtin and J. M. W. Turner, and formed the basis for a poem by Matthew Lewis in 1808.