Dumbarton Rock and Castle
Contents
![]() | View of Dumbarton Rock from the shore at Sandpoint |
The works cited in this article (using square brackets) are listed in a references

Geological origins
Dumbarton Rock is a volcanic plug. During the Carboniferous Period, there was a great deal of volcanic activity throughout the region. Remnants of many volcanic vents can be found within a strip that runs SW-NE from Dumbarton Rock to Fintry (NS6186), and which is about 27 kilometres long by about 2 to 3 kilometres wide.A few of the other volcanic plugs to be found within that strip are illustrated below:
![]() | ![]() | ![]() | (left & middle) Dumgoyne (right) Duncolm |
![]() | ![]() | ![]() | (left & middle) Dumbuck Hill (right) Dumbowie Hill |
![]() | ![]() | ![]() | (left) Dumgoyach (with Duntreath Standing Stones![]() (middle) Duncryne / the Dumpling (right) Lot's Wife, near the Gates of Sodom ![]() |
The abundant outflows from these volcanoes are called the Clyde Plateau Lavas, and they include the Kilpatrick Hills, the Campsies, and other ranges. More than seventy volcanic vents have been identified in the Kilpatrick and Campsie Hills, and they vary greatly in size (Lot's Wife, pictured above, is perhaps the smallest known example). Former volcanic vents may be filled with pyroclastic rocks, formed from material that was blown from the volcano and which landed nearby; on the other hand, when magma solidifies within the vent, it produces a basalt plug.
Dumbarton Rock itself is "a plug of microporphyritic olivine-basalt of Lower Carboniferous age" ([BGS], p52). This means that it is made of a fairly alkaline basalt, which contains small crystals of olivine within a finer-grained basalt matrix.
The dark basalt shows conspicuous columnar jointing, which is well seen from adjacent Castle Road

![]() | ![]() | ![]() | (left) Columnar jointing on the eastern side (middle) Columnar jointing on the western side (right) Concretion surrounded by calcite veins |
Despite the effects of erosion, many parts of the Clyde Plateau Lavas are still hundreds of metres thick. According to [BGS] (p108), they may originally have covered an area of about 3000 km², and they may have been 600 metres deep in places. This shows the scale of the volcanic activity that took place here. At present, at least thirty distinct lava flows, with a combined depth of 300 metres, can be identified on the steep escarpments of the Kilpatrick, Campsie, and Fintry-Gargunnock Hills ([Mitchell], p26).
![]() | The Long Crags: the escarpment of the Kilpatrick Hills; see also a wide-angle view from below |
Appearance
The Rock has two summits. The higher one, to the west, is the more pointed, and is called White Tower Crag, after a White Tower which stood there in the Middle Ages; this crag is about 74 metres (240 feet) high. The eastern peak is about 10 metres lower; it is called the Beak, and has a flatter summit area. A deep cleft between the two peaks provides a means of access to the upper parts of the Rock. Some natural terraces have provided suitable places on which to build.At its base the Rock is about 250 metres across from east to west, and almost as much from north to south.
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There are some very large stones at the western side of the Rock. The largest


History
Only the sketchiest of historical accounts is given below, with just a few events picked out from the Rock's many centuries of history. Even from this brief account, it should become clear that the castle has had an important role to play in Scotland's history. For those who wish to know more, the references
The Roman period
Ptolemy's "Geography" (2nd century AD) names some of the places and early peoples of Scotland. The River Clyde is recorded there as the Κλώτα (Clōtā); the river has therefore had essentially the same name from then to the present day. (Technical note: I have had to infer that the final "a" in Clōtā was long; by the rules of Greek accentuation, the word would have been written Κλῶτα, with a circumflex, if the final "α" was short.)At that time, Dumbarton Rock appears to have fallen within the territory of a people whom Ptolemy calls the Damnonii (sometimes spelled Dumnonii); their domain may have extended from the River Clyde to Manau (or Manaw: the plain at the head of the Firth of Forth), and northwards to Strathearn. See my article on Carman Hill for a more in-depth discussion of this topic.
The Britons who had a stronghold at Dumbarton were successors to (and perhaps the descendants of) the Damnonii who had earlier occupied this area.
Bede, in his "Ecclesiastical History of the English People" (completed about 731) mentions Dumbarton twice, although not by that name. In chapter 1, he describes "a very extensive arm of the sea", namely, the Firth of Clyde, which "runs inland from the west for a very great distance, where there stands Alcluith, a city of the Britons, strongly fortified to this day" ["civitas Brettonum munitissima usque hodie"]. In chapter 12, while discussing the Britons, he again mentions "the city of Alcluith, which in their language means 'the rock of Cluith', as it stands near a river of that name". The river is the Clyde (Ptolemy's "Clōta"), and the name Alcluith is British (a language very much like an early form of Welsh). Later, Gaelic became the dominant language in the area; the present-day name Dumbarton is from the Gaelic for "fort of Britons".
"Leven" and "Lennox":
Ptolemy also mentions a "Lemannonian gulf/inlet" (Λεμαννόνιος κόλπος), whose name appears to be based on the same root as that of the River Leven, which flows past the rock. Dumbarton lies within a large territory that was historically known as the Lennox (earlier "Levenax"), a derivative of "Leven". These names are from a Celtic root meaning "elm", for which the present-day Gaelic word is "leamhan". For references, see the link just given.
As for nearby Ben Lomond, Watson derives its name from a P-Celtic (akin to Welsh) word, "llumon" or similar, for a beacon or chimney; the name would then denote the "beacon mountain", perhaps simply indicating its prominence rather than its use.
At the time of writing, a few web pages maintain that the name of the River Leven means "smooth stream". However, that explanation is long out of date; see my description of the River Leven, and its footnotes, for further details and relevant references.
It is worth adding that some of the older works on the history of this area mention a Roman naval base called Theodosia at Dumbarton. This idea is fiction: it is one of several misconceptions that had their origins in a notorious forged work called "De Situ Britanniae". I discuss elsewhere, in a different article, the pervasive influence of that work on local history books.
The kingdom of Alt Clut
A useful modern reference for this period is [Fraser]. In the following, I adopt that author's practice of using the name "Alt Clut" to designate the early British kingdom that included the fortress of Clyde Rock (now called Dumbarton Rock).The Rock occupies a strategic location at the confluence of the rivers Leven and Clyde, and its topography favours its use as a fortress.
For evidence of early fortifications, see below, in the section on Archaeology


Aside from its conflicts, and notice of the death of some its rulers, we are told very little about the history of the kingdom of Alt Clut at this early period. Around the end of the sixth century, Riderch I of Alt Clut appears to have been involved in warfare against Bernicia (an Anglian kingdom). In 643, Domnall Brecc, a king of Dalriada, was killed at Strathcarron while fighting a British king, Eugein son of Beli (it is generally inferred that Eugein was a king of Alt Clut, even though none of the sources are explicit about this; see [Fraser], p173).
It is possible that Alt Clut was the successor of a kingdom that had, in the Roman period and later, included both Manau and Strathearn, and which corresponded to the domain of the Damnonii (mentioned above). By the latter half of the seventh century, the kingdom may have lost much of its former territory to the Picts or the Bernicians, or to both. Despite this, there is some evidence to suggest that Britons (most probably those of the kingdom of Alt Clut) were dominant in the west in the 670s and 680s.
In 750, in a battle at place called Mocetauc (probably

The Annals of Ulster (in Latin) record the "combustio" of "Alocluade" in 780, but the circumstances of this event are not described. For almost a century after this, the kingdom does not receive mention in the historical records, although this may simply reflect a lack of sources for that period.
In 870, Dumbarton Rock was besieged by the forces of Olaf the White (a Norse king of Dublin) and Ivar the Boneless. The defenders succumbed to the invading forces after four months, and the fortress was plundered and destroyed. After this event, we hear no more about Clyde Rock; instead, we hear (from 872 onwards) of the "kingdom of Strathclyde". The name change perhaps reflects a political reconfiguration of the northern Britons; it is widely believed that Dumbarton Rock was abandoned and that the new kingdom was based further up the River Clyde.
The subsequent history of the kingdom of Strathclyde is not relevant to the present account of Dumbarton Rock; it is sufficient to note here that the territory of that kingdom would become incorporated into the kingdom of Scotland by the eleventh century.
As for Dumbarton Rock itself, it does not re-emerge into history until the 13th century; its use, if any, in the years in between is not recorded. There are some incised cross-slabs at the Castle which date from the tenth century; they were found during excavation of a garden terrace behind the Governor's House. While it is possible that the stones are a relic of continuing occupation of the Rock, they may simply have been brought from elsewhere at a later date (for example, similar stones were found at Govan). In either case, they indicate a Christian presence in the wider area during the tenth century. (See [Alcock], p117-118.)
![]() | Ancient carved stones (except for the one at the lower right, which dates from 1704) |
"Coroticus":
The Harleian genealogies of the kings of Alcluith include a certain "Ceretic Guletic". Scholars generally (though not unanimously) identify this Ceretic with the Coroticus who, as recounted in Muirchu's "Life of Patrick", was strongly criticised by Patrick because of the actions of his war-band. Chapter headings were added to Muirchu's work over a century after it was completed, and the author of those headings made the same identification, calling Coroticus "regem Aloo", or king of Ail (thought to mean Clyde Rock), an expression which does not appear in the original text.
The subject is discussed by Simon Taylor in a chapter written by him ("Early History and Languages of West Dunbartonshire") in the book "Changing Identities, Ancient Roots" (2006).
Archaeology
At this point in the account, it would be appropriate to consider what has been revealed by archaeology.Leslie Alcock excavated the Beak (the flatter eastern summit of the Rock) in 1974-75; see [Alcock]. Before then, it was thought likely that the early fortifications at Dumbarton had been in the form of a "nuclear fort" (in other words, it consisted of an upper citadel with lower enclosures looping out from it); certain features visible on the ground were thought to be traces of this structure; however, the excavations revealed no evidence for such a nuclear fort (and the supposed traces on the ground turned out to be from a much later period).
![]() | ![]() | ![]() | (left) The eastern end of the Rock (middle) White Tower Crag from the Beak (right) The Beak from White Tower Crag |
Any archaeological investigation on the Rock is greatly hampered by the building and rebuilding that has taken place here since the Middle Ages. However, on the eastern spur of the Beak, Alcock did find traces of a timber-and-rubble rampart that had been destroyed by fire (possibly relating to the events of either 780 or 870). The reason for excavating the Beak was that, as Alcock writes, "the higher, western summit, the so-called White Tower, is too pointed for occupation as anything more than a look-out". Alcock suggested the possibility that the large hill fort of Carman had been the immediate precursor of the early fortress of Dumbarton Rock, Carman perhaps having been located inconveniently far from the sea (he made it clear that these were hypotheses only; Carman has never been excavated).
For much more information about the fort on Carman Hill, see my article about the hill.
![]() | ![]() | ![]() | Carman hill-fort: possible precursor to Dumbarton Rock |
Alcock's report is well worth reading: in addition to discussing the excavation and its findings, it provides an abundance of background information.
The new castle
From this point on, [MacPhail] is the best source of information.In 1222, by means of a charter of King Alexander II, the Royal Burgh of Dumbarton was founded; in the charter, the king mentions his "new castle" at Dumbarton (the castle and the new burgh belonged to the king, but they were located within the extensive domain of the Earl of Lennox). In the past, the name Dumbarton had primarily been associated with the Rock itself (much of the land that would be occupied by the royal burgh had formerly been known as "the lands of Murroch", a name that is still applied to a prominent burn), but the name Dumbarton now also applied to the burgh.
![]() | ![]() | ![]() | The Murroch Burn |
The first keeper (or constable) of the castle of whom we have historical notice is William Bisset, recorded as sheriff of Dumbarton in 1237. Our present-day lists of the keepers of the castle are based, in part, on information presented in the Dennistoun Manuscripts

William Wallace
When Edward I mounted his first invasion of Scotland in 1296; a certain Sir Ingram de Umfraville was constable of the castle, and he handed the keys to Edward. After William Wallace's victory at the battle of Stirling Bridge in 1297, the English garrison withdrew from Dumbarton Castle, and Wallace had three English knights clapped in irons there; they were the first named prisoners whom we know to have been held in the castle (their names were William FitzWarin, Marmaduke Tweng or Thweng, and William de Ros).A later keeper of the castle was John Menteith ("the fause Menteith"), infamous for his instrumental role in Wallace's capture. It is a measure of how much confidence the English King (Edward I) had in Menteith that Edward felt safe in entrusting Menteith, a Scot, with holding this important fortress for him. There is a tradition that a leering carved stone face on the castle's Guard House represents Menteith (of course, there is no way to determine whether that tradition is correct).
There are also the remains of a "Wallace Tower" on the Rock; the structure was probably named in honour of the great patriot, although it dates from a later period. Opinions differ on whether Wallace himself was ever held at the Castle; on the one hand, the 1958 version of the Castle's official guide-book states that "it is improbable that Wallace was detained in the castle"; on the other, MacPhail states that "although there is no record of Wallace's confinement in the castle after his capture, this was most likely to have happened as Sir John Menteith, who was sheriff of Dumbarton and keeper of the castle, was responsible for having him transported to London; but it could only have been for a day or so, as Wallace was brought to trial in Westminster Hall a little over three weeks from the date of his capture" [MacPhail, p15-16].
![]() | ![]() | (left) Guard House detail: traditionally, the 'fause Menteith' (right) The National Wallace Monument |
The Wallace Sword


Robert the Bruce
In 1306, the recently-crowned Robert the Bruce demanded that the above-mentioned Sir John Menteith surrender Dumbarton Castle to him. Menteith refused to surrender the castle unless Bruce brought a letter signed with King Edward's great seal. However, at some point after Edward's death, Menteith surrendered the castle to Bruce, and found it expedient to declare the latter to be the true heir of Alexander III.In 1320, a certain Sir William de Soules was found to have conspired to remove Robert from the throne; de Soules was subsequently imprisoned in Dumbarton Castle, and he died shortly thereafter. In 1321, Bruce rewarded the loyalty of Malcolm, Earl of Lennox, with the hereditary keepership of Dumbarton Castle.
Second War of Scottish Independence
During the minority of David II, Edward Balliol, with support from the English king Edward III, briefly gained control over much of Scotland. Many of Scotland's leaders were killed at the Battle of Halidon Hill in 1333, and the young king David was himself taken to Dumbarton Castle for his protection in that year; in 1334 he and his young bride departed from there for France. Scotland's position seemed weak, yet Balliol would soon be deposed by the loyal followers of David II; David himself returned to Scotland in 1341. During this period, Scotland's successful fightback was due in no small measure to the effective campaign of resistance carried out by Sir Andrew Moray of Bothwell, Guardian of Scotland.Later history
When James I of Scotland returned, in 1424, from a long captivity in England, he stripped Sir Walter Stewart (son of Murdoch Stewart, Duke of Albany) of the keepership of Dumbarton Castle (Sir Walter would be beheaded in 1425), and appointed John Colquhoun as keeper in his stead. This John Colquhoun died in 1439, but, after a tempestuous period in the minority of James II, Sir John Colquhoun of Luss was keeper of the castle for several years from 1455 onwards. He cared for this assignment well, and James III would appoint him keeper of the castle for life in 1474 (although, as it happened, Colquhoun died not long afterwards).James III was defeated in 1488, at the Battle of Sauchieburn, by an army of disaffected nobles that included his own son, the future James IV. The latter, on his accession to the throne, had to deal with a divided kingdom, and he twice besieged Dumbarton castle in 1489. After its capture, a relative of Robert Blackadder (Bishop of Glasgow) briefly held the position of keeper of the castle, but a few years later this position passed to Matthew Stewart, the Second Earl of Lennox.
Later, James IV would use Dumbarton as a base from which to launch his expeditions against the troublesome Lords of the Isles. After James died at the Battle of Flodden in 1513, Scotland once again had a king in his minority, and, as before, rival factions vied for power. In 1514, the young John Stewart, Fourth Earl of Lennox, a nephew of the Earl of Arran, seized Dumbarton Castle in order to strengthen his own position and that of his uncle. He and his followers did so by burrowing under the North Entry under cover of darkness (at that time, the castle still had a northern entrance), and ejecting the garrison.
It was from Dumbarton Castle that Mary, Queen of Scots, departed Scotland for France in 1548. After her return, the castle was held by Mary's supporters against those of her infant son James VI. It was taken by James' supporters in 1571 when Captain Thomas Crawfurd of Jordanhill

(Crawfurd's large memorial is located beside the Auld Kirk at Kilbirnie; it is the box-like structure that can be seen on the left in a picture

After 1603, the Castle had less strategic importance than before and mainly served as a prison fortress. One notable prisoner was Patrick Stewart

When Charles I tried to impose a new prayer book on Scotland, he faced a great deal of opposition; his authority was defied by a General Assembly of the Scottish Kirk in Glasgow. Charles planned to invade Scotland to enforce his authority, and Dumbarton was to be the landing place for troops from Ireland. However, the king's plans for Dumbarton were forestalled when the Provost of Dumbarton, John Sempill, captured the castle in 1639. As a result of this and other setbacks, Charles was compelled to sign a treaty, the Pacification of Berwick.
In 1725, General Wade visited the castle and found the defences in need of improvement. In 1727 he ordered the rebuilding of a section of rampart that had fallen away, and he increased the size of the garrison. At about the same time, fears of a Jacobite invasion provided the impetus for a more comprehensive reconstruction of the fortifications: the modifications included the building of the Governor's House and King George's Battery (both in 1735). [For the dates of other structures on the Rock, see the individual photographs of them, below, in features of the castle

Visitors
Although its military importance gradually declined, the castle increasingly became a visitor attraction.When Queen Victoria visited in 1847, the castle guns were fired in welcome. This startled the horses of the royal carriage, but they were brought under control before any further mishap resulted.
Another noteworthy visitor was Dr Samuel Johnson (on the 28th of October, 1773); he is said to have had some difficulty removing himself from the little sentry box near the Magazine. In 1803, William and Dorothy Wordsworth, in company with Coleridge, visited the castle; afterwards, they walked around the base of the Rock at low water.
![]() | ![]() | (left) This sentry box was a tight squeeze for Dr Johnson (right) The Wordsworths and Coleridge discussed this boulder (Click on those pictures for more details) |
Pier Park
Construction of Dumbarton Pier began in May 1874, on the south side of the Rock. It was originally known as the Clyde Pier, and it was completed in May of 1875. According to contemporary newspaper accounts of the opening, it was "constructed entirely of pitch pine", and extended "765 feet from the base of the Castle Rock". It was built while Samuel Bennett
A little later, in 1877, the engine


The presentation took place in the Pier Park on Saturday the 11th of August 1877; on that day, the engine was unveiled and officially handed over to the town. The accompanying festivities included a regatta, as well as various sporting events on the shore. Some who were not taking part in these activities looked on from a high vantage point, on top of the Rock.
![]() | ![]() | (left) Pier Park (right) Pier Park. The Castle was closed; note the scaffolding on the Governor's House. |
The engine remained in the Pier Park for a number of years, but it has subsequently been moved twice. After the first move, it became the centrepiece of a fountain pool in Dumbarton's shopping centre (an area that has changed greatly since then; the pool was at NS 3958 7533


![]() | ![]() | (left) Pier Park, from the Castle (right) The engine of PS Leven, in its present (2015) location |
Dumbarton Pier itself had never proved very popular; it could only be used safely at high water. It was severely damaged by gales in December 1900, and was never repaired; its remains were eventually removed.
Modern times
By the start of the twentieth century, the Castle was no longer of any great military importance, and it was gradually falling into disrepair.The War Office formally handed over the castle to the Office of Works in 1909, and it is now cared for as a scheduled monument; the full title of the 1958 version of the official guidebook is "Dumbarton Castle: Ministry of Public Building and Works Official Guidebook".
This ancient fortress had a final military role to play during the Second World War, when an anti-aircraft battery was installed on Dumbarton Rock. Four high-explosive bombs landed on the Rock in May of 1941. There was some damage to its structures (for example, the Magazine was hit, although, fortunately, it had long ceased to be used for its original purpose), but there were no casualties. No traces of the gun emplacements are visible.
At present (2015), Dumbarton Castle is in the care of Historic Scotland.
Features of the castle
Click on the individual photographs for further details. For further information, the souvenir guides listed in the references
The portcullis arch is thought to be the oldest of the surviving medieval structures. It protected the southern approach to the flat area between the two summits, and its top also served as a bridge, making it easier to get from one peak to the other.
On a pillar on White Tower Crag is a modern toposcope (a plaque showing the directions and distances of various hills and other landmarks).
Around that pillar are the remains of a circular structure

![]() | ![]() | ![]() | (left) Toposcope on White Tower Crag (middle & right) Remains of circular structure |
![]() | ![]() | ![]() | (left) Steep slopes of White Tower Crag (middle) The path to the top (right) A view down the same path |
![]() | ![]() | ![]() | (left) A second and much less conspicuous carved head on the Guard House (middle) Inside the Magazine (right) The Spur Battery |
![]() | ![]() | ![]() | (left) Steps to the well-house; the well used to be open, but it was covered over in the 18th century (middle) The covered well is behind this grate (right) An ancient spring on this slope finally dried up in the late 19th century because of work carried out nearby |
![]() | ![]() | ![]() | (left) This slot accommodated the portcullis; the portcullis itself was later replaced by a heavy gate, now gone (middle) The windows of an earlier Magazine; they can be seen in context in a view ![]() (right) There used to be several more buildings on the level ground between the peaks |
![]() | ![]() | ![]() | (left) The Duke of York's Battery (middle) The former site of the Castle's crane (right) The southern part of the Beak |
References
- [MacPhail] "Dumbarton Castle" (I. M. M. MacPhail, 1979):
as Alcock's report (see below) says, this is a "well researched and documented account of Dumbarton Castle". This is the most useful reference for the history of the castle from the founding of the royal burgh of Dumbarton down to the time of writing, and it recounts far more of the Rock's history than I give in the present article.
- [Fraser] "From Caledonia to Pictland – Scotland to 795" (James E. Fraser, 2009):
the first volume of The New Edinburgh History of Scotland. There are references to the kingdom of Alt Clut scattered throughout the work.
- [Woolf] "From Pictland to Alba – 789-1070" (Alex Woolf, 2007):
the second volume of The New Edinburgh History of Scotland.
- [Alcock] Proceedings of the Society of Antiquaries of Scotland (PSAS), volume 120 (1990), pages 95-149:
this is Leslie and Elizabeth Alcock's report on the excavation at Dumbarton Rock. The title of the paper is "Reconnaissance excavations on Early Historic fortifications and other royal sites in Scotland, 1974-84: 4, Excavations at Alt Clut, Clyde Rock, Strathclyde, 1974-75".
- [BGS] "British Regional Geology: The Midland Valley of Scotland" (British Geological Survey; 3rd edition, 1985):
this book was consulted for information on the Clyde Plateau Lava fields.
- [Mitchell] "Loch Lomondside" (John Mitchell, 2001):
part of the New Naturalist series, this book includes a discussion of the geology of the area.
- "Geological Features of Dumbarton Rock: A Geological Trail":
a very useful leaflet produced by Strathclyde Geoconservation Group (formerly known as Strathclyde RIGS Group).
- "Geology Explained Around Glasgow and South-West Scotland, Including Arran" (Judith A. Lawson & James D. Lawson, 1976):
chapter 3 includes a discussion of the geology of Dumbarton Rock; it also describes features of geological interest to be seen at the base of the Rock, on the western side.
- "Dumbarton Castle: Official Souvenir Guide" (Historic Scotland, editions of 1993 and 2007):
these are very useful accounts, in booklet form, of the visible features of the castle, and of its history.
- "Dumbarton Castle: Ministry of Public Building and Works Official Guide-book" (Iain MacIvor, Inspector of Ancient Monuments, 1958; HMSO, Edinburgh):
an earlier version of the guidebook, useful both by itself and in comparison with the later versions.
- "Warlords and Holy Men – Scotland AD 80-1000" (Alfred P. Smythe, 1984):
this is not so recent an account as Fraser's or Woolf's, but it is still of interest (see [Woolf], p353).
- "Historic Dumbarton" (E. Patricia Dennison & Russel Coleman, 1999):
this book is mainly intended for local authorities or others who may need to know of sensitive areas of archaeological interest within the historic burgh that might be affected by development. However, it is also useful to the non-specialist who is interested in the archaeology of the area. Pages 10-11 and 71-78 give an account of the Rock and its castle.