CRANNOG (Celt. crann, a tree), the term applied in Scotland and Ireland to the stockaded islands so numerous in ancient times in the lochs of both countries. The existence of these lake-dwellings in Scotland was first made known by John Mackinlay, a fellow of the Society of Antiquaries of Scotland, in a letter sent to George Chalmers, the author of Caledonia, in 1813, describing two crannogs, or fortified islands in Bute. The crannog of Lagore, the first discovered in Ireland, was examined and described by Sir William Wilde in 1840. But it was not until after the discovery of the pile-villages of the Swiss lakes, in 1853, had drawn public attention to the subject of lake-dwellings, that the crannogs of Scotland and Ireland were systematically investigated.
The results of these investigations show that they have little in common with the Swiss lake-dwellings, except that they are placed in lakes. Few examples are known in England, although over a hundred and fifty have been examined in Ireland, and more than half that number in Scotland. As a rule they have been constructed on islets or shallows in the lochs, which have been adapted for occupation, and fortified by single or double lines of stockaded defences drawn round the margin. To enlarge the area, or raise the surface-level where that was necessary, layers of logs, brushwood, heather and ferns were piled on the shallow, and consolidated with gravel and stones. Over all there was laid a layer of earth, a floor of logs or a pavement of flagstones. In rare instances the body of the work is entirely of stones, the stockaded defence and the huts within its enclosure being the only parts constructed of timber. Occasionally a bridge of logs, or a causeway of stones, formed a communication with the shore, but often the only means of getting to and from the island was by canoes hollowed out of a single tree. Remains of huts of logs, or of wattled work, are often found within the enclosure. Three crannogs in Dowalton Loch, Wigtownshire, examined by Lord Lovaine in 1863, were found to be constructed of layers of fern and birch and hazel branches, mixed with boulders and penetrated by oak piles, while above all there was a surface layer of stones and soil. The remains of the stockade round the margin were of vertical piles mortised into horizontal bars, and secured by pegs in the mortised holes. The crannog of Lochlee, near Tarbolton, Ayrshire, explored by Dr R. Munro in 1878, was 100 ft. in diameter, and had a double row of piles, bound by horizontal stretchers with square mortise-holes, enclosing an area 60 ft. in diameter. In the centre was a space 40 ft. square, bounded by the remains of a wooden wall and paved inside with split logs. A partition divided it into two equal parts, one of which had a doorway opening to the south, and close by it an extensive refuse-heap. In the middle of the other part was a stone-paved hearth, with remains of three former hearths underneath. The substructure was built up from the bottom of the loch, partly of brushwood but chiefly of logs and trunks of trees with the branches lopped off, placed in layers, each disposed transversely or obliquely across the one below it. A crannog in Loch-an-Dhugael, Balinakill, Argyllshire, described by the same explorer in 1893, revealed a substructure similar to that at Lochlee, with a double row of piles enclosing an area 45 to 50 ft. in diameter, within which was a circular construction 32 ft. in diameter, which had been supported by a large central post and about twenty uprights ranged round the circumference.
From their common feature of a substructure of brushwood and logs built up from the bottom, the crannogs have been classed as fascine-dwellings, to distinguish them from the typical pile-dwellings of the earlier periods in Switzerland, whose platforms are supported by piles driven into the bed of the lake. The crannog of Cloonfinlough in Connaught had a triple stockade of oak piles, connected by horizontal stretchers and enclosing an area 130 ft. in diameter, laid with trunks of oak trees. In the crannog of Lagore, county Meath, there were about 150 cartloads of bones, chiefly of oxen, deer, sheep and swine, the refuse of the food of the occupants. In the crannog of Lisnacroghera, county Antrim, iron swords, with sheaths of thin bronze ornamented with scrolls characteristic of the Late Celtic style, iron daggers, an iron spear-head 16½ in. in length, and pieces of what are called large caldrons of iron, were found. Among the few remains of lacustrine settlements in England and Wales, some are suggestive of the typical crannog structure. The most important of these is the Glastonbury lake village, excavated by Mr A. Bulleid and Mr St George Gray. It consists of more than sixty separate dwellings, grouped within a triangular palisaded defence, formed in the midst of a marsh now partially reclaimed. The dwellings were circular, from 18 to 35 ft. in diameter, the substructure formed of logs and brushwood mingled with stones and clay, and outlined by piles driven into the bottom of the shallow lake. The walls of the houses seem to have been made of wattle-work, supported by posts sometimes not more than a single foot apart. The floors are of clay, with a hearth of stones in the centre, often showing several renewals over the original. The relics recovered show unmistakably that the occupation must be dated within the Iron Age, but probably pre-Roman, as no evidence of contact with Roman civilization has been discovered. The stage of civilization indicated is nevertheless not a low one. Besides the implements and weapons of iron there are fibulae and brooches of bronze, weaving combs and spindle-whorls, a bronze mirror and tweezers, wheel-made pottery as well as hand-made, ornamented with Late Celtic patterns, a bowl of thin bronze decorated with bosses, the nave of a wooden wheel with holes for twelve spokes, and a dug-out canoe. Another site in Holderness, Yorkshire, examined by Mr Boynton in 1881, yielded evidence of fascine construction, with suggestions of occupation in the latter part of the Bronze Age. Similar indications are adduced by Professor Boyd Dawkins from the site on Barton Mere. On the other hand, the implements and weapons found in the Scottish and Irish crannogs are usually of iron, or, if objects of bronze and stone are found, they are commonly such as were in use in the Iron Age. Crannogs are frequently referred to in the Irish annals. Under the year 848 the Annals of the Four Masters record the burning of the island of Lough Gabhor (the crannog of Lagore), and the same stronghold is noticed as again destroyed by the Danes in 933. Under the year 1246 it is recorded that Turlough O’Connor made his escape from the crannog of Lough Leisi, and drowned his keepers. Many other entries occur in the succeeding centuries. In the register of the privy council of Scotland, April 14, 1608, it is ordered that “the haill houssis of defence, strongholds, and crannokis in the Yllis (the western isles) pertaining to Angus M’Conneill of Dunnyvaig and Hector M’Cloyne of Dowart sal be delyverit to His Majestie.” Judging from the historical evidence of their late continuance, and from the character of the relics found in them, the crannogs may be included among the latest prehistoric strongholds, reaching their greatest development in early historic times, and surviving through the middle ages. In Ireland, Sir William Wilde has assigned their range approximately to the period between the 9th and 16th centuries; while Dr Munro holds that the vast majority of them, both in Ireland and in Scotland, were not only inhabited, but constructed during the Iron Age, and that their period of greatest development was as far posterior to Roman civilization as that of the Swiss Pfahlbauten was anterior to it. (See Lake Dwellings.)
Authorities.—Dr R. Munro, The Lake Dwellings of Europe: being the Rhind Lectures in Archaeology for 1888 (with a bibliography of the subject) (London, 1890); Ancient Scottish Lake-Dwellings or Crannogs (Edinburgh, 1882); Col. W. G. Wood-Martin, The Lake-Dwellings of Ireland, or Ancient Lacustrine Habitations of Erin, commonly called Crannogs (Dublin, 1886); Sir W. Wilde, Descriptive Catalogue of the Antiquities in the Museum of the Royal Irish Academy, article “Crannogs,” pp. 220-233 (Dublin, 1857); John Stuart, “Scottish Artificial Islands or Crannogs,” in the Proceedings of the Society of Antiquaries of Scotland, vol. vi. (Edinburgh, 1865); A. Bulleid, “The Lake Village near Glastonbury,” in Proceedings of the Somersetshire Archaeological Society, vol. xl. (1894). (J. An.)