The Gaelic word dùn (pronounced doon) means ‘fort, castle, fortified hill’. It is found in place-names including Dundonald ‘Donald’s fort’ in Ayrshire, Dunbeg ‘small fort’ near Oban on the west coast of Scotland, An Dun Mhor ‘the big fort’ on the island of Arran, Dunduff ‘black fort’ in Ayrshire and Dun an Ruigh Ruadh ‘fort of the red slope’, beside Loch Broom in Western Scotland.
Some place-names containing the word dùn are likely to be very old, dating to the earliest stratum of Gaelic naming in Scotland. For example, Dunragit ‘fort of Rheged’ in Galloway contains the name of a Brythonic-speaking kingdom which flourished in Southern Scotland and Northern England between the fifth and the eighth centuries. Similarly, Dumbarton ‘fort of the Britons’ on the Clyde refers to Dumbarton Rock, which was the capital of the Brythonic kingdom of Strathclyde, and Dunkeld ‘fort of the Caledonians’ refers to a site associated with a Pictish-speaking tribe who lived in Northern Scotland.
The Brythonic language contains a cognate form din, also meaning ‘fort’, and some Gaelic names in dùn may be partial translations of older Brythonic forms. For instance, the Gaelic form of the name Edinburgh is Dùn Èideann ‘fort of Eidyn’ which appears to be a translation of the Brythonic form Din Eidyn, first recorded in the famous Welsh poem Y Gododdin. Additionally, the name Dunbar ‘summit fort’ in East Lothian is likely to have been a translation of an earlier Brythonic name Din-bar with the same meaning. Hill names such as Din Fell and Din Law in the Scottish Borders also appear to contain the Brythonic form of the word, with the Scots words fell ‘a rocky hill’ and law ‘a rounded hill’ being later additions to these names.
In the case of Dumbarton above, the dun– form has evolved into dum-, and this is because it is easier to pronounce dum– than dun– in front of certain consonants. Other examples include Dumfries ‘fort of the copse’, Dumbreck ‘speckled fort’ and Dumgoyne ‘arrow fort’, both of which are in the Campsie Fells to the north of Glasgow.
Dùn is also attested in the diminutive form dùnan, meaning ‘a small fort, a fortlet’, with examples including Dunan ‘fortlet’ on the island of Skye, Dùnan liath ‘grey fortlet’ in Ross and Cromarty, and Dunan Mor ‘big fortlet’ and Dunan Beag ‘little fortlet’, the sites of two Megalithic chambered cairns on the island of Arran.
There is another Gaelic word with a similar meaning to dùn. The word caisteal (pronounced kash-tyall) means ‘castle, stone fort’. It is found in place-names including Caisteal Nan Con ‘castle of the hounds’ on the island of Mull, Caisteal Fliuch ‘wet castle’ on the island of Arran, Caisteal Breac ‘speckled castle’ on the Ardnamurchan peninsula, Caisteal Nan Caillich ‘castle of the old woman’ in Aberdeenshire and Caisteal na Nighinn Ruaidhe ‘castle of the red haired maiden’ on the small island of Innis Luana in Loch Avich in Argyll. The ruins of a castle are still visible on the island, which was once a stronghold of the Clan Campbell.
The word caisteal is also attested as a qualifying element in place-names, with examples including Torr a’ Chaisteal ‘mound of the castle’, which is the site of an Iron Age fort on the island of Arran, and Creag a’ Chaisteal ‘crag of the castle’ on the island of Mull, which is also the site of a fort. There is a stone circle at Allt a’ Chaisteil ‘burn of the castle’ in Sutherland, and Leac a’ Chaisteil ‘ledge of the castle’ refers to a rocky hill on the island of Mull. There are also two mountains named Beinn a’ Chaisteil ‘mountain of the castle’, one on the edge of Argyll and the other in Ross and Cromarty.
A variant form of caisteal is caiseal, which is found in place-names such as Cashel ‘castle’ on the banks of Loch Lomond, Cashel Dhu ‘black castle’ in Sutherland, Tom Chaiseil ‘knoll of the castle’, in Perthshire and Craigcaiseal ‘castle rock’ in Stirlingshire.
Not all of the caisteal or caiseal names refer to a literal castle. In some cases, hills which are shaped like a castle, or have the appearance of an impregnable or commanding position, have also been named caisteal. The mountain An Caisteal ‘the castle’ in Stirlingshire is likely to have been named because of its shape, and Caisteil na Cloinne ‘the children’s castle’ near Gairloch in Wester Ross was apparently the name given to a large rock full of holes in which children would play.
However, in many cases, the element does refer to an actual castle. Caisteal Maol ‘bare castle’ is the name of a ruined hill-top castle which belonged to the Clan Mackinnon on the island of Skye, and the current name may reflect the ruinous state of the castle. The older name of this castle was Dùn Akin ‘Haakon’s fort or castle’, and this may be a reference to King Haakon IV of Norway, who is believed to anchored his fleet here prior to his defeat at the Battle of Largs in 1263.
References & Further Information
Peter Drummond, Scottish Hill-Names: Their Origin and Meaning (2007)
John Murray, Reading the Gaelic Landscape (2014)
W.J. Watson, The History of the Celtic Place-Names of Scotland (2011, 1926)
W.J. Watson, Place Names of Ross and Cromarty (1904)