From La Tène D1b (c. 100 BCE), the site experienced a notable expansion to the east, encompassing approximately fifty hectares. This makes it the largest identified oppidum in Indre-et-Loire, with other sites not exceeding ten hectares in size. Moreover, the entire oppidum surface seems to have been continuously inhabited, which is uncommon for structures of this magnitude. The site, structured as a genuine urban center, attained considerable commercial, religious, and presumably political importance. The Châteliers oppidum is also among the twenty largest in France.
A massive earth rampart Situated 900 meters from the promontory's extremity, but exhibits characteristics associated with the "Fécamp-type" ramparts. In 1978, the rampart was cut through by a road, revealing its internal structure. The base of this cross-section consists of an initial clay embankment with charcoal inclusions and possibly a wooden framework. The embankment is approximately 10 meters wide and seems to have been built during
La Tène A or B1 (c. 400 BCE). However, its exact function remains undetermined, as it may have served as a primitive rampart or another construction. The rampart was significantly elevated during La Tène D by successive additions, reaching a height of approximately 10 meters and a width of 25–30 meters. To the east, a flat-bottomed ditch, 40 meters wide, continues the natural dry
valley of Malvau in the northern part of the structure. In 1986, the remains of the rampart and its ditch were designated as historic monuments.
An urbanization layout still to be determined The remains discovered at the site indicate the presence of a rational spatial structure, with roads (ditched paths) oriented in an east-west and north-south configuration. Artisanal activities that were perceived as a nuisance (butchery, pottery, ironwork, and possibly tanneries) were situated on the periphery of the plateau, while the "noble" crafts (precious metalworking,
glassmaking) were located in the central area, near the residential zones. The highest point on the plateau, situated in the center, encompassed at least three hectares and was designated for religious and public activities. Two potential east-west routes, identified through
aerial surveys, may have survived into modern times as a rural path (in the center of the site) and a street (at the extreme south, on the edge of the plateau). The presence of
tegulae fragments along their paths lends support to this hypothesis. The structures that enabled the crossing of the rampart have yet to be discovered.
An active religious life A cluster of temples The initial monumental
fanum-type temple was unearthed in 1980. The structure is oriented eastward and encompasses a square
cella, encased within a gallery, at the center of an
enclosure measuring approximately 45 meters in diameter. The north wall of the enclosure, constructed on a terrace, is reinforced internally by
discharge arches to distribute the pressure exerted by the surrounding earth. The entire vases were deposited at this level, suggesting they were part of a ritual practice. The stone walls have undergone significant deterioration, with almost all of them having disappeared. It seems probable that this
fanum is a reconstruction, up to the 2nd century, of an earlier structure dated to the last third of the 1st century BCE. The temple's ornamentation included painted geometric designs and a mosaic fragment. However, the most luxurious elements were systematically salvaged during its dismantling, resulting in the loss of significant historical value. To preserve the archaeological potential of the area, all construction work was halted in 1994, and the land was purchased by the
Ministry of Culture A rectangular structure, which may have been used for ritual purposes, is situated close to this temple to the north of the enclosure, Two additional fana, exhibiting reduced cella dimensions, were unearthed in 1995 ?) from statuette. It is not feasible to delineate the specific cults observed at Ambacia, whether they were conducted in public settings within temples or in private contexts within households. Nevertheless, the discovery of six
sandstone statuettes, measuring between 15 and 35 cm in height, on the site in varying states of preservation, with the majority dating to the 1st century BCE, may provide insight into the deities worshipped. One of the statuettes depicts a figure with a face that has been deliberately mutilated, accompanied by a horned animal (believed to be a goat or stag) that is often associated with
Cernunnos. Another
anthropomorphic statuette, adorned with a
torque on its neck and holding another in its right hand, is linked to the same symbolism. The head of a third statuette (the only part preserved) recalls the finesse of the goddess
Epona. A vase from the early decades of the current era appears to have contained a medicinal preparation described approximately fifty years later by
Pliny the Elder. This vase was modified (with perforations and graffiti), presumably for ritual purposes, to prevent its reuse as a container. The documentation of funerary practices within the context of the Gaulish city is incomplete and insufficient. A burial, presumed to be in an earthen grave, situated to the south of the site, has been dated to a period between 176 and 50 BCE. It is noteworthy that the burial occurred within the city limits, contrary to local customs. This area was not heavily urbanized at the time, which may indicate that the deceased held a particular social status and was granted a privilege. Despite increasing urbanization over the following centuries, this tomb was respected. The presence of human bones, primarily skulls, outside burial contexts suggests that they were prepared shortly after death, with the bones cleaned and stripped.
Intense artisanal and commercial activity Initially, commercial exchanges occurred over short distances or within specific regions, such as
Morvan and the
Massif Central, until approximately 50 BCE. Thereafter, they became more intense and diversified, extending to regions including
Franche-Comté, the ,
Tuscany, Campania, and
Tarraconensis. Concurrently, the assortment of imported commodities at Ambacia grew in both number and diversity. These included items such as
Sicilian alum for
tanning hides,
Egyptian
natron for glassmaking, tableware, and wine from Italy or Spain. However, local production of consumable goods was given preference when feasible. The artifacts unearthed at the site provide evidence that the artisans of Ambacia adopted techniques from other regions. This is particularly evident in the locally produced pottery, which, beginning in the late 1st century BCE, began to emulate the forms and decorations of the luxury pottery produced in Campania. There are a limited number of surviving examples of artisan installations. These were constructed using wood and earth and are thought to have been destroyed by subsequent developments. The artifacts associated with these activities include weavers'
weights, bronze molds, metal and glass fragments, butchered animal bones, and woodworking tools. Several pottery kilns were identified within the site, with the most recent discovery occurring in 2018 at the base of Caesar's mound. This kiln, which was likely in use for a relatively brief period, has been dated to between 30 BCE and 20 CE. This estimation is based on the structure of the kiln and the products that were produced (plates, goblets, and vases). Such a type of kiln, which has a heating chamber that is slightly over one meter in diameter, is generally found only in areas that have been heavily
Romanized. Between 1982 and 1983, archaeologists made an important discovery: perforated plates that closely resembled the molds of a minting workshop. The discovery of similar artifacts at numerous settlement sites indicates the possibility that these are bronze ingot foundries. In the absence of locally minted coins (such as the Turones bronze coin stamped TVRONOS/TRICCOS dating to around 40 BCE, discovered at Châteliers in the nineteenth century), the majority originate from other regions of Gaul, particularly neighboring territories (
Bituriges,
Carnutes, or
Pictones). The remaining
coins were from territories with which Ambacia had trade relations. In addition to minted coins,
cast potin coins with a "diabolic head" design were prevalent. An inventory published in 2018 revealed that of the 1,267 coins collected on-site, 1,258 were pre-medieval, and 1,071 were Gaulish potins.
Domestic arrangements still poorly understood A post-built dwelling of 37 m² was confirmed at Châteliers. It is noteworthy that such discoveries are rare, due to the perishable nature of the materials used and the rapid disappearance of remains as the site was reused. At
Ambacia, housing structures are indicated by the accompanying
pits, as well as by the discovery of household items (fire dogs, keys, and cabinet door hinges), and by negative imprints of wooden post holes supporting constructions. The stone grinding mills for domestic use indicate that producing flour could be conducted on an individual basis within family housing units. The mills were sourced from workshops with established locations in
Saint-Christophe-le-Chaudry, situated approximately 150 km from
Amboise. The discovery of a considerable number of animal bones across the site provides evidence of a high consumption of butchered meat, predominantly beef, and pork, along with some mutton, goat, and potentially dog. The proportions of these meats varied by inhabited area, suggesting the presence of different social strata. Animal slaughter possibly occurred in a ritual context. Despite the Loire River and nearby forests, consumption of wild game from fishing (fish) or hunting (
deer) was rare, which aligns with dietary habits observed elsewhere. Additionally, the large number of amphora fragments that transported wine—a costly imported product—suggests that some
Ambacia inhabitants had a high social status. Many structures resembling wells, with a maximum depth of six meters and some exhibiting indications of wooden lining, have been identified on the plateau. In the absence of an existing or fossil water
table, it is more probable that these were cisterns intended to collect runoff water. A well with a depth of five meters was previously reported in 1890; however, its precise location on the site was not identified. Other partially or completely buried structures are interpreted as cellars for smaller ones and as larger storage caves. An openwork handle crafted from an enameled metal alloy, potentially associated with a strainer, was unearthed near a metalworking workshop. Radiocarbon dating suggests that it dates to the conclusion of the La Tène period or the onset of the Augustan period. Its probable function is linked to various, yet poorly understood, domestic activities at the
Ambacia site during that era. The handle appears to have been produced locally. == Antiquity:
Ambacia and
Caesarodunum, two cities for one
civitas ==