The present volume, 26th of the series Cahiers d'archéologie jurassienne, presents the Bronze and Iron ages finds and features discovered at Combe En Vaillard, Combe Varu and Combe Ronde. These three sites, located near the village of Chevenez in the Ajoie region (Canton Jura, Switzerland), were excavated between 1998 and 2003 prior to the construction of the A16 Transjurane motorway.

After the short introductory chapter 1 follows a description of the geology of each site, completed by some observations on the evolution of the local hydrology and climate during the Bronze and Iron ages (chap. 2). The following chapters 3 to 5 present the archaeological finds and structures site by site. A concluding synthesis forms the sixth and last chapter.

This publication throws a new, if imperfect light on the settlement of this region between the Late Bronze Age and the beginning of the gallo-roman period. Although the investigated sites are not well preserved, it was nonetheless possible to document the presence of small and isolated occupations within each site during the Late Iron Age. These rural and mostly agricultural settlements consist of one or more rectangular one-aisled buildings with several construction phases in some cases. Hearths and a variety of pits, mostly of indeterminate function, accompany the buildings. The architectural remains observed on the three sites are not specific enough to identify any regional building traditions. In Combe Varu and Combe Ronde, human remains belonging to a small number of immature individuals were also discovered.

Potsherds make up the majority of the artefacts. Metal is rare or absent. The oldest occupations are characterised by a small repertory of pottery shapes, apparently typical of a local production that often used fossil shell temper. The Early La Tène site of Alle - Noir Bois, located in the same district, does not contain any shell-tempered ware, which first occurs in the Ajoie during the Middle La Tène and disappears at the end of the gallo-roman period. In the Late La Tène assemblages, the presence of imported pottery, fibulae of the Nauheim type and glass bracelets indicates the development of an extensive trade network. Several typical and well-dated artefacts seem to have appeared simultaneously in the large Late La Tène settlements and in our rural context. In economic terms, the finds seem to indicate a considerable degree of self-sufficiency. The faunal remains include both domestic and wild animals. The spectrum of the faunal remains and the exploitation or preparation of particular species vary however between the sites. This variation may in part be due to the different chronology of the settlements. The archaeobotanical analysis shows that wild plants continue to be gathered in parallel with cereal farming, confirming observations made on several contemporary sites located on the Swiss plateau. As at Alle - Noir Bois, millet is the main cultivar, probably because it is well suited for the soils of the Ajoie region. Textile production and leatherworking complete this panorama of domestic and agricultural activities. At Combe En Vaillard, the discovery of two smithies underlines the important part ironworking must have played in the economy of that settlement.

The sites discovered near Chevenez improve our understanding of the late prehistoric settlement density and organisation within the Ajoie region. They also throw a new light on the regional exchange network of the Late Iron Age. This new information pertains for the most part to the chronological period following the abandonment of Alle - Noir Bois ; the results of research under way at Alle - Les Aiges and in the valley of Delémont will soon further add to our understanding of this time. Together, these sites allow us to open a window on a period of prehistory that, though well documented around the large settlement centers, remains largely unexplored in our rural region.

Translation: Robert Fellner