The Châteauneuf enclosure, also known as the "Martinopole enclosure," is a fortification wall that surrounded the settlement of Châteauneuf-de-Saint-Martin, now integrated into the modern city of Tours, located in the Indre-et-Loire department in the Centre-Val de Loire region of France.
The enclosure was likely constructed in the early 10th century to provide physical protection for the Basilica of Saint Martin and to assert the political presence of the settlement that developed around the sanctuary, in opposition to the nearby Gallo-Roman city. Surrounded by a defensive ditch and equipped with gates and towers, the enclosure became obsolete with the construction of a newer wall encompassing a larger area. It was gradually dismantled, with its materials repurposed. The last significant above-ground remains were destroyed during World War II and postwar reconstruction. Two restored towers remain visible to the east and southwest, and additional remnants survive underground.
The enclosed town comprised two distinct communities. The southern sector was occupied by the canons of the collegiate church of Saint Martin, forming the canonical quarter, while the northern sector was inhabited by lay residents. No physical barrier appears to have separated the two groups, which coexisted along a shared street.
The Châteauneuf enclosure has been listed as a historic monument in the national register since the period between 1940 and 1950, with the designation dates varying by section.
Historical and political context
A city in early bipolarity
At the beginning of the 10th century, the city of Tours, as it is recognized today, did not exist as a unified urban entity. Instead, two distinct centers, separated by over a kilometer, coexisted with their own identities:
To the east was the Cité of Tours, a successor to the Roman city of Caesarodunum. Enclosed by 4th-century castrum walls, it hosted both comital (administrative) and episcopal (religious) authorities but lacked significant economic activity.
To the west, a settlement developed around the tomb of Saint Martin, gradually expanding due to the growth of pilgrimage activity and the accumulation of land donations. The sanctuary's royal protection enhanced its prestige. Originating from the 5th-century basilica constructed over the saint’s tomb and elevated to a collegiate church shortly after the Fifth Council of Aachen in 817, the town expanded northward, forming a suburbium and likely establishing a landing stage on the left bank of the Loire. At this stage, the area lacked a defensive enclosure.
Between the two urban centers, development was limited, with the exception of the declining monastery of Saint-Julien, which was later revitalized by Archbishop .
A defensive structure with symbolic purpose
The wealth and prominence of the town surrounding the Basilica of Saint Martin—encompassing both its merchant population and the chapter of the Collegiate Church of Saint Martin of Tours—provoked significant interest and envy. Between November 8, 853, and June 30, 903, the area experienced multiple Norman incursions, resulting in pillaging and fires. These events led to the temporary relocation of Saint Martin’s relics to several sites, including the Abbey of Saint-Paul de Cormery, the Collegiate Church of Léré, the Martinian villa in Chablis, and eventually the Cité of Tours. While contemporary chronicles tend to exaggerate the scale of these attacks, they nonetheless contributed to a climate of insecurity. In response, the canons, merchants, and bourgeois of the town financed the construction of a defensive enclosure around the Basilica of Saint Martin. Although protection was the officially stated purpose, the initiative also appears to have served broader political and religious objectives.: Le castellum sancti Martini (903-938)
The construction of the enclosure was part of a broader contest for influence among local authorities. It sought to assert the identity of the new Martinian town in contrast to the older urban center, amid often difficult relations between the basilica chapter and the count, and especially the bishop. This tension became more pronounced from the late 10th century onward.: La Martinopole The architectural choice to emulate the ancient castrum—still prominent in the 10th century—suggests that Châteauneuf aimed to position itself as equal to the older city. The enclosure formalized the city's bipolar structure at the close of the early Middle Ages, particularly as episcopal influence extended both east and west of Châteauneuf, placing it between the possessions and spheres of influence of its rival. By encompassing both religious and secular areas, the enclosure also reinforced the mixed and enduring character of the settlement.
A construction with uncertain chronology
Until the mid-2000s, most historians, following the interpretation proposed by in 1970, held that the fortification of Châteauneuf occurred in two distinct phases. According to this view, an initial enclosure composed of a wooden palisade and an external ditch was constructed in the early 10th century. This structure was subsequently replaced by a masonry fortification at the end of the 10th century or the beginning of the 11th century, generally following the same layout. This hypothesis was supported by the term castrum nuovum sancti Martini, in which the adjective nuovum was understood to signify that a "new" enclosure had superseded an earlier one.
Since 2007, a re-examination of written sources and a reinterpretation of field data have led to a reassessment of the previously accepted chronology. The existence of an initial enclosure made of perishable materials, for which no archaeological evidence has been found, is now considered uncertain. Current interpretations suggest that the fortification of Châteauneuf may have been constructed in a single phase, directly in stone, between 903 and 918. This construction would have followed authorization granted by King Charles the Simple in a charter issued at the joint request of Robert (Count of Tours, son of Robert the Strong and lay abbot of Saint-Martin from 888 to 902: Relations politiques et responsabilités au sein du chapitre de Saint-Martin (du IXe siècle à la fin du Xe siècle) and the local townspeople.: Les remparts
The term "Châteauneuf" appears to have been used in a pejorative sense by the monks of Marmoutier, likely to highlight the greater antiquity of their own Martinian foundation in contrast to this newer district. The designation castrum novum occurs earliest and most frequently in charters and documents originating from Marmoutier. In contrast, documents from the chapter of Saint-Martin do not use the term castrum; from the 10th century onward, they refer instead to claustrum or castellum Sancti Martini to more specifically denote the canonical enclosure. The term "Martinopole" is attested only briefly at the end of the 11th century, possibly influenced by Bérenger of Tours, who aimed—without success—to establish a major district under the spiritual authority of Saint Martin.: Martinopolis
General layout and design
The outline of the Châteauneuf enclosure is approximately defined by the perimeter formed by Rue Néricault-Destouches to the south, Place Gaston-Paillhou and to the west, Rue de la Rôtisserie and Rue du Petit-Soleil to the north, and Rue du Président-Merville and Rue de Jérusalem to the east. These streets, already present in the Middle Ages, were initially thought to have served as service paths bordering the exterior of the ditch.: Les remparts However, they possibly occupy the ditch’s original location. The wall’s layout appears to have been influenced by pre-existing spatial structures, such as roads and land plots, although this cannot be confirmed with certainty. A north-south route between the wall and the Loire, attested as early as the 7th or 8th century, may have been reorganized in the early 10th century by Archbishop Téotolon to improve access between the enclosure and the river. This route then divided into multiple branches upon exiting the northern boundary of the enclosure.
In 1888, proposed the existence of an inner rampart within the Châteauneuf enclosure, closely surrounding the basilica to provide additional protection for the Martinian sanctuary. This hypothesis, likely based on a misinterpretation of archaeological evidence, is not supported by contemporary chronicles and is contradicted by accounts of the 1417 assault on Châteauneuf by John the Fearless, which confirm the absence of such a fortification.
The eastern section of the enclosure is relatively well documented, owing to archaeological investigations conducted after the destruction caused by World War II. The northern face can be partially reconstructed from parcel boundaries visible in the Napoleonic cadastre.: Remparts et ponts : heurs et malheurs The western flank had largely disappeared by the 18th century, and changes in the parcel layout before the cadastre make its precise tracing difficult. The southern section, once preserved and maintained, now survives only in fragmentary form, either through physical remnants or historical plans. However, these elements enable a partial reconstruction of its original extent.: Les remparts
Architecture
The general architecture of the Châteauneuf enclosure, characterized by its curtain walls and towers, appears to have been inspired by the Gallo-Roman enclosure of Tours, dating back to the 4th century. It features regularly spaced towers integrated into a high and thick curtain wall, using brick or terracotta in certain architectural elements, including the arches of some openings.
Curtain wall The construction of the Châteauneuf enclosure features faced walls composed of small, irregular masonry, primarily flint bonded with pink mortar, and coated with a secondary layer of pink or reddish mortar. This coating, sometimes revealing the white tips of the rubble stones, may reflect an aesthetic consideration. The outer facings enclose a rubble fill core, with the wall measuring approximately 2.5 to 3 meters in width and potentially reaching a height of 10 to 11 meters above the medieval ground level. The foundations, though difficult to access, appear to be made of large stone blocks. An excavation in 1889 indicated that the ground level had risen by approximately 6 meters between the 10th and late 19th centuries. The presence of a wall walk remains uncertain, although in 1941, referenced “a stone staircase [that] is almost certainly the one that provided access to the walls.”
By the mid-11th century, the northern section of the Châteauneuf curtain wall appears to have been neglected, while the southern portion, corresponding to the canonical enclosure, continued to be maintained. From the 12th century onward, segments of the wall were repurposed as foundations for houses built along its outer face, primarily by lay residents, but also by clergy. During this period, the defensive function of the enclosure progressively declined. In the 14th century, parts of the wall were dismantled and used as a quarry for building the clouaison constructed under John the Good, which rendered the Châteauneuf enclosure obsolete as it was incorporated within the new fortification. Surviving sections of the wall were either demolished when they impeded new construction or reused as structural elements within buildings.
A map of Tours dating from around 1670, attributed to Tonon de Rochefou, shows the approximate outline of the former enclosure based on the alignment of interior streets, although the curtain wall itself is no longer depicted.
Gates