1° In Limousin, our knowledge of ancient monumentalfuneral architecture has been given a new impetus forresearch during the past fifteen years thanks to the inventoryof large-stone blocks reused in civil and religious constructionsor even in later funeral arrangements.2° It is from this standpoint that the Châteauponsac sitehas been included where, in an urban landscape, a largeconcentration of examples of ancient architecture areconserved. Among the major facilities preserving in theirelevations a large number of these re-used stones is includedthe ancient Saint-Thyrse abbey church and the Porte Peyrine ,which unlike the neighbouring religious building, has so farbeen the subject of no specific study.3° The Châteauponsac site is in a privileged topographicalposition, since human occupation is concentrated in aninterfluve zone between two valleys, that of the Semme to thenorth and that of the Gartempe to the south. These naturalconditions, with the relatively steep slopes and the sharpecurve of the embanked meander of the Gartempe, constitute a place for a permanent, easily defensible establishment.Although, until now, known for its three medieval ecclesialpoles, a human occupation from Antiquity has long beenrecognized. In the Merovingian period, the existence of twotrientes constitute the first mention relating to Châteauponsac.However, the question of the precise location of the castrumPotentiacum was still posed, which led to consider severalsectors of the city in relation to the topography, writtensources and available archaeological witnesses.4° Textual sources, essentially modern, provide only afragmentary vision of a Late Middle Ages fortification.Nevertheless, several indications are provided by the ditches,towers and the names of the entrances to the city. Amongstthe four main restored entry points the Porte Peyrine is absent.Although local scholarship traditionally associates it with thefortification work carried out between 1420 and 1454, itsperiod of construction has always remained uncertain. Thisis why it appeared timely to initiate a first study taking intoaccount the archaeological potential and the marginal placeoccupied by this monumental gate in the urban fabric.5° Except for modern transformations, in particular theaddition of a high hall covered with a gable roof, thesustaining walls in the western span and the semicirculararch in the eastern span, the Porte Peyrine conserves all of itsinitial volume.This massive construction, reinforced in thenorthwest and southwest by thick masonry, has a relativelysimple plan, barlong with a floor area of almost 15 m2.Thisspace is subdivided into two unequal parts lengthwise - 3 mfor the eastern corridor versus 2 m for the western one -,separated by jambs 0.60 m high and 0.50 m wide. To thedetriment of the eastern access, where only the two southernsidewall/jamb foundations are visible, the frame of theintermediate door is complete with its jambs marked by achamfered jutting lower base, corbelled imposts andmonolithic lintel. These two entries were initially closed by adouble door attested by the circular traces left by the rotationaxes. The fortified passage initially had a floor “built” of largeflat stones, located 0.30 m below the current circulationlevel. This monumental pavement is intersected by twohollows with divergent orientations, probably both sepulchralas evidenced by the burial in a coffin of perishable material- oriented south-north -, deposited in a pit cut in the rock anddelimited laterally by small “low walls”. The tomb wasradiocarbon dated to between 779 and 969 A.D. whichprovides a terminus post quem for the construction of the door6° The different archaeological approaches have made itpossible to demonstrate that this monumental element is farfrom being isolated, since several segments of the curtainwall have been identified in the elevations of the adjoiningcivil structure, of which almost 25 m have been conserved.The sections studied allow reconstitution of an enclosure atleast 2.60 m wide and 3 m high equivalent to seven coursesof large stone blocks. There is a visible difference between thenorth and south curtain walls. On the southern side, thefacings are characterized by a specific implementation: thefoundations consist of four jutting foundations to the east ofthin elongated blocks, while in elevation there is analternation of rows of large blocks and rows of significantlysmaller ones. On the northern side, the builders tried torationalize foundation heights. Regarding blocking masonry(north and south), it is made of piled-up rough local stonesof various sizes and shapes. It is undoubtedly economic andtechnical reasons, more than aesthetic, which explain thisconstruction. The majority of the upper level blocks havebroken angles - deterioration linked either to a brutaldismantling of ancient buildings, or to the removal of themetal ties at a later period –also many of them bore traces ofthe anchoring systems used to lift, assemble and clamp,unlike the lower rows.Although these different indices reflectancient construction processes, it is difficult to determinewhether these were specifically designed for the erection ofthe fortification. If this is not the case, it suggests animmediate re-use of these elements and why not a deliberatedestruction of the original buildings. The use and assemblyof this type of stone element are found on other sites such asPérigueux, Saintes or even Bordeaux, where the vestiges ofthe enclosures have been dated to the Late Roman Empire.7° This combination of archaeological studies has madeit possible to discern in the urban landscape of Châteauponsaca unique fortified structure, whose chronology, traditionallydated to the beginning of the 15th century, was revised to beearlier,and at the earliest Late Antiquity, at the latest theHigh Middle Ages before the 7th century, if one accepts thenumismatic references Potincacocas (tro) or Potenciaco c. Itsabandonment phase, which is not better understood, isperhaps linked to the coal seams of the seventh and eighthcenturies identified in the Saint-Thyrse church. A profoundreorganization of the urban space seems nevertheless to havetaken place during the Carolingian period, with the probableenlargement of the funeray space up to the Porte Peyrine. Atthe beginning of the eighteenth century, the fortification wasincorporated into the new civil building .8° A true unicum in Limousin, since the Limoges ancientcastrum wall is known only through a later written source, thismonumental group is part of a phenomenon, now wellidentified, that of the re-use of ancient materials in the ofmausoleum type funerary buildings, as attested by theepigraphic sources. However, the question of its functionremains without it being possible to privilege certainhypotheses (vicus protected by a fortification, presence of astaging post monitoring the crossing of the Gartempe, amilitary fort located near an important crossroads built fromLate Antiquity and transformed over the following centuriesinto a place of economic power,…?).9° Despite a large number of uncertainties on its layout,its organs (towers, access) and use the first results contributeto increase our understanding of the genesis of Châteauponsacand its morphological evolution, and in particularreconsideration of the initial nucleus around the church ofSaint-Martin. This study also makes it possible to enrich theparticularly sparse corpus of fortified sites of Late Antiquityor the High Middle Ages in South-West France.
La mise en évidence dans le tissu urbain du bourg deChâteauponsac (Haute-Vienne) d’une construction monumentaleencore existante sur plus de 25 m de long,aujourd’hui intégrée en grande partie dans les constructionsactuelles et peu visible, a été interprétée, après un travail derelevé et de sondages archéologiques, comme une fortificationde l’Antiquité tardive ou du haut Moyen Âge. Construit avecdes blocs monumentaux, cet ouvrage défensif conserveencore en élévation une porte complète.
