Between 1993 and 2001 a British team led by S. Esmonde Geary, M. J. Jones and the author examined the Late-Roman defences of the ‘ville haute’ of Saint-Bertrand-de-Comminges (SW France). The project fell within the overall theme of studying the transition from the classical to the late antique/early mediaeval town, a principal objective of the international Trojet Collectif de Recherches’ at Saint-Bertrand. The primary aim of the British investigation was to document and analyse the construction of the Late-Roman defences and their subsequent development through a combination of architectural survey and excavation. During the nine seasons of fieldwork, the architectural remains of the entire wall circuit were analysed and 11 separate trenches excavated. The evidence obtained from these excavations dates the wall's construction to the early years of the 5th c.The architectural survey included collating old photographs and unpublished excavation records; preparing a plan showing the surviving original and rebuilt stretches of the walls; making a general survey of the principal external and internal elevations, and recording the outline of all visible Roman facing and corework, vertical and horizontal breaks, offsets, tile courses, drains, re-used masonry and later building and repairs; making stone-by-stone drawings of the best surviving elevations and features; making a detailed analysis of the wall fabric, interpreting its building periods and phases of construction, and identifying changes in alignment of the defences, the presence of external towers, work-gang divisions, and so on. For ease of reference, the circuit was divided into 26 sectors on the basis of criteria such as change of alignment and state of preservation.
