by government troops. Flora MacDonald, who helped Bonnie Prince Charlie to escape from Scotland, was briefly imprisoned here while en route to imprisonment in London. According to W. Douglas Simpson the castle appears in Tobias Smollet's Humphry Clinker, which although not naming Dunstaffnage, presents "a fair picture of life in the castle in the third quarter of the eighteenth century". Decline and restoration The Campbells continued to add to the castle, building a new house over the old west range in 1725. However, the rest of the castle was already decaying. In 1810 an accidental fire gutted the gatehouse, and the Captains ceased to live here, moving to Dunstaffnage House some 2 km to the south-east. Tenants lived in the 1725 house within the castle until 1888. Restoration work was undertaken in 1903 by the Duke of Argyll, the castle's owner. This was followed in 1912 by a court case, in which the Court of Session ruled that Angus Campbell, the 20th hereditary Captain, had right of residence notwithstanding the Duke of Argyll's ownership. Works were delayed by World War I, and the planned total restoration was never completed. In 1958, the 21st Captain and the Duke agreed to hand the castle into state care, and it is now open to the public as a Historic Environment Scotland property. Description Walls Dunstaffnage is an irregular quadrangular structure of great strength, with rounded towers at three of the angles. It measures approximately , and has a circumference of about . The walls are of coursed rubble, with sandstone dressings, and stand up to 18 m (60 ft) high, including the conglomerate bedrock platform. The walls are up to 3 m (10 ft) thick, affording strong defence to this highly strategic location, guarding the entrance to Loch Etive and the Pass of Brander beyond, and today commanding a splendid view. The parapet walk, which once followed the whole of the walls, has been partially restored with new stone flags. The original parapet is now also gone. Arrow slits, later converted into gunloops, are the only openings. Brass cannon recovered from wrecked vessels of the Spanish Armada were once mounted on the walls. Round towers Soon after the construction of the castle walls, three round towers were built on the north, east, and west towers. The north tower, or donjon, is the largest, comprising three or four storeys originally, and probably housed the