Most appear on the Buildings at Risk register, and no owner is known for some. While a number are due to be renovated, the battle to bring these once-mighty piles back to use is far from won.
1. Dunans Castle, Strachur, Argyll.
Dunans was the former seat of Fletchers of Dunans, who acquired the pile after the 1745 Jacobite rebellion. It is said to be in a 'very poor condition' but its restoration is being funded partly by the sale of portions of ground with 'Laird and Lady' titles. PIC: Creative Commons/Slink Pink.
2. Glendevon Castle, Perthshire
Built in the 1760s, the castle was later used as The Dungeon restaurant but has stood empty for almost 30 years and is now in a poor condition with its owner not known. PIC: YouTube/RobertSmith.
3. Mearns Castle, Newton Mearns, East Renfrewshire
This 15th Century tower house was built for the powerful band of Maxwell knights. Now owned by the Church of Scotland, it sits in a poor condition and is riddled with damp. PIC: geograph.org/wrobison.
4. Kinloch Castle, Isle of Rum
This castle was once the ultimate Victorian pleasure palace built for wealthy English industrialists. Today, its future is extremely uncertain with renovation to cost at least 7m and a community takeover bid recently unsuccessful. PIC: TSPL.