The ancestral seat of the Sutherland family for more than 500 years, Duffus is one of the best examples of a 12th century Norman motte and bailey castle in Scotland. It was originally surrounded by the swampy foreshore of the now drained Spynie Loch, making it one of the most secure fortifications in the land. However, the man-made mound couldn’t take the weight of a large stone tower built on it during 14th century.

This caused it to subside, break off, and slip down the mound. Further evidence of the site’s instability is illustrated by the contraction of large windows to reduce the unsupported open spaces.