Threave Castle sits on an island in the river Dee about 2 miles from the town that bears its name. The castle, which is owned by Historic Scotland is reached only by boat. Further information can be found on http://www.undiscoveredscotland.co.uk/castledouglas/threavecastle/index.html.

Caerlaverock Castle is situated south of Dumfries and is well worth a visit. Further information can be found on www.undiscoveredscotland.co.uk/dumfries/caerlaverock/index.html