Souterrain (from Frenchsous terrain [fr], meaning "subterrain", is a name given byarchaeologists to a type of underground structure associated mainly with the European AtlanticIron Age.
These structures appear to have been brought northwards fromGaul during the late Iron Age. Regional names includeearth houses,fogous andPictish houses. The termsouterrain has been used as a distinct term fromfogou meaning 'cave'.[1] InCornwall the regional name offogou (Cornish for 'cave') is applied to souterrain structures.[2][3] The design of underground structures has been shown to differ among regions; for example, in western Cornwall the design and function of the fogou appears to correlate with a larder use.[4]
The namesouterrain comes from theFrench language (sous-terrain orsouterrain), in which it means "underground passageway" or refers tosubterranea in general. In languages other than English, it is sometimes used to mean "basement", especially in warehouses, orsemi-basement.
Souterrains are underground galleries and, in their early stages, were always associated with a settlement. The galleries were dug out and then lined with stone slabs or wood before being reburied. In cases where they were cut into rock this was not always necessary. They do not appear to have been used for burial or ritual purposes and it has been suggested that they were food stores or hiding places during times of strife, although some of them would have had very obvious entrances.[5]
An example of a wood-lined Iron Age souterrain with a possible water tank was excavated in 2016 at Brechin Farm,Angus byHeadland Archaeology. It was 15 metres (50 feet) in total length and was constructed in a 'C' shape with two distinct chambers. A linear ditch was located immediately adjacent to the souterrain and was connected to the southwest chamber by a tunnel. This tunnel sloped gently downwards towards the chamber and its edges were iron-panned, indicating that water had run through it for a significant amount of time. This indicates the southwest chamber was used as some kind of water collection and storage system. The soil into which the souterrain was dug was soft sand that would have been impossible to maintain without a lining; the presence of stake holes along the edge of the northeast chamber and the lack of stones means that the walls would have been wood-lined. Radiocarbon dating suggests occupation between the 1st and 3rd centuries AD.[6]
An example of an excavated souterrain is the site atRosal,Strathnaver,Sutherland.[7] In this excavation, noartefacts or other finds were made inside the structure and the roof may have been only partially covered with stones, a timber roof being present on part of it. It was suggested that the souterrain could have been used as abyre or barn and it was associated with an abandoned settlement.
An example of a partially explored souterrain in northernScotland, onShapinsay in theOrkney Islands isCastle Bloody, situated near the seacoast.[8] Another example has been excavated in Perthshire nearAlyth.[9]
In Scotland some souterrains may be connected with the same people who builtbrochs.
A well-illustrated account of a souterrain excavated at Newtownbalregan,County Louth, one of the many souterrains discovered during a road-building project in Ireland, may be found inArchaeology Ireland Winter 2003 issue.[10]
A full report on the excavation of a three-level souterrain at Farrandreg, County Louth, in 1998 gives references for the 14 souterrains previously excavated in this souterrain-rich county.[11] Finds included a rotaryquern-stone (a grinding stone), a bone comb, a copper-alloy stick pin, three bone needles and the greater part of a tub-shaped pottery vessel in ‘Souterrain ware.’ Based on the finds, the excavator concluded the souterrain had been closed up in the 12th century.
Souterrains often are referred to in Ireland simply as ‘caves.’ A. T. Lucas, a folklorist and director of the National Museum of Ireland in the 1960s, published a series of articles on the references to souterrains in the earlyIrish annals.[12]Donaghmore Souterrain, discovered in County Louth in 1960, andDrumlohan Souterrain in County Waterford are the only souterrains to be an IrishNational Monument.
In Ireland, souterrains often are found inside or in close proximity to aringfort and as such are thought to be mainly contemporary with them, making them somewhat later in date than in other countries. This date is reinforced by many examples whereogham stones dating to around the 6th century have been reused as roofing lintels or door posts, most notably at the widened natural limestone fissure at the ‘Cave of the Cats’ inRathcrogan. The distribution of souterrains is very uneven in Ireland, with the greatest concentrations occurring in north Louth, north Antrim, south Galway, and west Cork and Kerry. Lesser numbers are found in counties Meath, Westmeath, Mayo, north Donegal, and Waterford. Other counties, such as Limerick, Carlow, and Wexford, are almost completely lacking in examples.[13]
An article by Warner on the archaeology of souterrains, although published 46 years ago, still is possibly the best general overview of the subject.[14]
The most comprehensive study of Irish souterrains is M. Clinton's 2001 work, containing chapters on distribution, associated settlements, function, finds, chronology and 13 appendices on various structural aspects of souterrains.[13]
A short summary account of souterrains in Ireland appeared in the quarterly magazineArchaeology Ireland in 2004.[15]