Dumbarton Castle (Scottish Gaelic: Dùn Breatainn, pronounced [d̪̊unˈb̊ɾʲɛhd̪̊ɪɲ]) has the longest recorded history of any stronghold in Great Britain. It overlooks the Scottish town of Dumbarton, and sits on a plug of volcanic basalt known as Dumbarton Rock which is 240 feet (73 m) high.