The Environmental Context and Function of Burnt-Mounds: New Studies of Irish Fulachtaí Fiadh

Burnt mounds, or fulachtaí fiadh as they are known in Ireland, are probably the most common prehistoric site type in Ireland and Britain. Typically Middle to late Bronze in age (although both earlier and later examples are known), they are artefact-poor and rarely associated with settlements. They generally consist of a low mound of stones often showing signs of fire-exposure arranged by, or around, a pit or trough, which may be unlined or lined by wood or stone. The function of these sites has been much debated with the most commonly cited uses being for cooking, as steam baths or saunas, for brewing, tanning or textile processing. A number of major infrastructural development schemes in Ireland in the years 2002-2007 revealed remarkable numbers of these mounds often associated with wood-lined troughs, many of which were extremely well preserved. This afforded an opportunity to investigate these sites as landscape features using
environmental techniques - specifically plant macrofossils and charcoal, pollen, beetles and multielement analyses. This paper summarises the results from eight sites from Ireland and compares them with burnt mound sites in Great Britain. The fulachtaí fiadh which are generally in clusters are all groundwater-fed by springs along floodplains and at the bases of slopes. The sites are associated with the clearance of wet woodland for fuel and have predominantly ‘natural’ beetle assemblages typical of wet woodlands. Seven out of the eight sites had evidence of nearby agricultural (arable) and all sites revealed low levels of grazing. At one site (Cahiracon) both pollen and coleoptera suggested that oak galls or leaves were brought onto site, at another (Coonagh West) both pollen and macrofossils suggested that alder was being used on site. Multi-element analysis at two sites (Inchagreenoge and Coonagh West) revealed elevated heavy metal concentrations suggesting that off-site soil, ash or urine had been used in the trough. This evidence, taken together with the shallow
depth of all the sites, their self-filling nature, attempts to filter incoming water, the occasional occurrence of flat stones and flimsy stake structures at one site (Inchagreenoge), suggests that the most likely function for these sites is textile production involving both cleaning and/or dyeing of wool and/or natural plant fibres. This can be regarded as a functionally related activity to hide
cleaning and tanning for which there is evidence from one site (Ballygawley) as well as other Irish burnt mound sites. Whilst further research is clearly needed to confirm if fulachtaí fiadh are part of the ‘textile revolution’ we should also recognise their important role in the rapid deforestation of the wetter parts of primary woodland and the expansion of agriculture into marginal areas during the Irish Bronze Age.