Archaeology of earthen architecture in the western Mediterranean, with particular regard to southern France

Lecture by Dr Alessandro Peinetti – Dipartimento di Storia Culture Civiltà, Università di Bologna.

Contributors: Alessandro Peinetti (Inrap, Auvergne – Rhône-Alpes, France; UMR 5140 ASM ; Università di Bologna); Emilie Leal (Inrap, Midi-Méditerranée; UMR 5140 ASM); Julia Wattez (Inrap, Centre – Ile-de-France ; UMR 5140 ASM)

Archaeology of earthen architecture in the western Mediterranean, with particular regard to southern France: field detection, chaîne opératoire characterization and socio-cultural perspectives

A Raw earth has been widely used since Neolithic times, and is still the most widely used building material in the world today. It is estimated that a third of humanity lives in an earthen dwelling. Earthen architecture, whether simple or monumental, can be found in a variety of contexts and meets a wide range of needs. Raw earth is also a material widely used in European vernacular architecture in its various forms: mudbrick, cut out sod, rammed earth, cob, wattle and daub, floors construction and furniture shaping. Although obscured in today’s urban and rural landscape, earth materials have always been used for architectural purposes, sometimes in association with other materials (wood, stone), both in continental and northern Europe and around the Mediterranean.

In the early 1980s, a keen interest in building with raw earth developed in France as part of archaeological research, in parallel with the rise of an architectural movement that wanted to promote building processes based on this material, which also had an ecological and social dimension (see, for example, the work of CRATERRE).

In archaeology, excavations carried out at the Iron Age site of Lattara (Lattes, Hérault) in the 1980s and 1990s led to the identification of mudbrick and cob architectures. These discoveries made a major contribution to boosting research into earthen architecture in southern France and raising awareness among a whole generation of researchers about the identification and technological characterisation of this type of architecture. The end of the twentieth century and the 2000s marked a new turning point in research, particularly in the field of preventive archaeology at Inrap (Institut national d’archéologie preventive). This research led to the discovery of earthen buildings from the Neolithic period in Languedoc and Provence, as well as 13th and 14th century houses built entirely of raw earth, many of which are still standing today (fig. 2). Later, preventive archaeology excavations have also identified the use of earthen materials in the layout of burial spaces from the Neolithic to the Iron Age, showing how the use of these materials goes beyond the simple domestic sphere. It is now a proven fact that raw earth is used in every field of construction: military (ramparts), all kind of private or economic dwellings (warehouse, wine cellars …) or funeral field. The example of the preventive excavation of the Late Neolithic semi-grounded architecture of the collective burial of Mas Rouge (Montpellier, Hérault) is exemplary in this respect (main image). Researches into the use of raw earth in Roman times are also currently under development and deeply renews our vision of the ancient city where obviously raw earth constructions are the main part of the domestic architecture.

Over the last twenty-five years, the organisation of a series of round-tables dedicated to transdisciplinary researches on raw earth constructions (Échanges transdisciplinaires sur les constructions en terre crue) has made it possible to establish the terminology used in architectural and technological analysis, as well as to raise issues relating to the development of the constructive cultures of earthen architecture.

Research carried out on archaeological sites in temperate, mediterranean or tropical climates has highlighted the difficulties of identifying and technologically characterising these architectures. These problems arise as early as the fieldwork phase. Effectively, earthen architectures are often heavily levelled or buried under rubbles, resulting from its deterioration and demolition, causing identification problems that can be solved thanks to the use of suitable excavation protocols and an accurate knowledge of the principles of raw construction.

The way in which these architectural remains are viewed has evolved, leading to the integration of architectural analysis with geoarchaeological studies using micromorphology as a tool for characterising materials and their manufacturing and installation processes. All this work, highlighting the archaeological potential of such areas, has gone beyond the boundaries of French archaeology and has had an impact, to varying degrees, on the development of research into raw earth in the Western Mediterranean.

It is clear that the identification of a particular construction technique is not an end in itself. Understanding the potential for adaptation within a single technology, the place of this material next to stone or wood and which economic system (from material supply to recycling) it fits into, helps to define the socio-economic and cultural characteristics of particular human groups or territory. It turns out that not all earth-based construction techniques were invented or used everywhere. Although some are indeed “universal”, others were developed in specific places. They were then transmitted and spread through the movement of populations or craftsmen and through voluntary or forced borrowing. These processes have either endured or been abandoned in the course of history.

Research into earthen architecture is therefore central to the study of the development of local building cultures and their development, from the Neolithic to the present day, in the western Mediterranean basin and neighbouring areas.

Main image: Mas Rouge (Monpellier, Hérault, France): detail of the burial layers with raw earth elements of the Late Neolithic collective burial of Mas Rouge (credits Y. Tchéremissinoff).