Gallo-Roman Baths of Alauna: A Roman Bath Complex in France
Site at a Glance
- Rating
- 4.2
- Popularity
- Low
- Country
- France
- Primary era
- Classical
- Eras represented
- Classical
- Civilizations
- Roman
- Site type
- Sanitation
- Remains
- Baths
On this page15 sections
History
The Gallo-Roman baths of Alauna are a Roman-period bath complex in France, within the modern town of Valognes. Built by the Gallo-Roman culture of Gaul, which combined Roman institutions and technologies with local traditions, they were probably constructed between AD 60 and 80 during the expansion of Alauna and the building of its principal monuments. Their early date places them before the major growth of bath complexes in Gaul during the Antonine period, the era of the Roman dynasty that ruled from AD 96 to 192.
Construction and Roman use
The baths stood in the northern part of Alauna, close to the town’s principal north-south road, probably the cardo maximus. This major Roman street continued north toward Fermanville and possibly Cherbourg. The building occupied the lowest part of the settlement, near the northwestern edge of the city and close to the foot of the plateau above the Merderet valley.
Ditches initially bounded the plot and were partly filled when construction began. A brick kiln, a well, and another masonry structure belong to the early Roman activity associated with the building works. The complex itself appears to have retained its original general design. Latrines were later added beside the western wall near the water inlet, and an external pool may have been connected to the same room, although the dates of these changes are unknown.
The baths went out of use toward the end of the third century as Alauna declined. During the following centuries, their masonry was dismantled and reused in other buildings. The site remained active again only toward the end of the Middle Ages, when a hamlet developed there. Some of its buildings were founded on the western walls of the baths, while stone was recovered elsewhere, including from the foundations. This varied reuse helped preserve the elevated parts of the Roman structure by incorporating them into later buildings that were eventually demolished.
Recognition and investigation
By 1688, the ruins were linked with a tradition concerning an ancient city and the so-called Old Castle. Some traditions attributed that castle to Clovis, the Frankish king associated with the establishment of the Merovingian dynasty, but this attribution was not established. In 1695, Nicolas-Joseph Foucault commissioned excavations supervised by the Jesuit Pierre-Joseph Dunod. Dunod recognized the remains as an ancient bathhouse rather than a castle.
An incorrect plan published by Bernard de Montfaucon in 1722 showed the baths at Vieux-la-Romaine instead of Alauna. Although Montfaucon later corrected the mistake, the original plan continued to be reused, including by Jean-Louis Adam in 1905. Albert Grenier emphasized the importance of the correction in 1953. More accurate drawings and partial plans had already been published in 1765 by Anne Claude de Caylus, based on work by the engineer René Cevet.
In 1772 and 1773, the landowner attempted to destroy the ruins with explosives and artillery. The walls that stood at substantial height largely survived, while floors, underfloor heating systems, weaker wall sections, and parts of the foundations were damaged. Charles de Gerville resumed investigations in the early 1840s, compared the surviving fabric with earlier plans, and identified traces of the aqueduct that supplied the baths. The Normandy Antiquarian Society continued the work in 1845, although the landowner refused its members access to the complex.
The baths were classified as a French historical monument in 1862. They and the wider archaeological site of Alauna escaped the intense bombardment that devastated Valognes in June 1944 during the Normandy campaign. Surveys carried out between 1954 and 1968 were followed by consolidation of the remains. At the request of Valognes, a complete excavation took place from 1989 to 1992. It established the full plan of the complex and clarified its chronology in preparation for its development as an archaeological garden.
A multidisciplinary research program launched in 2012 by the National Centre for Scientific Research, the University of Caen-Normandy, and the French National Institute for Preventive Archaeological Research led to ground-penetrating radar surveys around the baths in 2020. These investigations are gradually revealing probable annexes in the immediate surroundings. The baths and the ancient theatre at Lillebonne are identified as the only Roman-period remains in Normandy preserved in elevation.
Remains
Plan and principal bathing rooms
The complex covered about 1,225 square metres in a square measuring 36.5 metres on each side. Its dimensions correspond to an actus quadratus, a Roman square unit measuring 120 Roman feet per side. The plan was divided into three modules from north to south and four from east to west, with the rooms arranged symmetrically around an east-west central axis.
Central bathing sequence
From east to west, the axis contained an apsidal cold pool, a frigidarium or cold bathing room, a caldarium or hot room with a hot pool, and a sudatorium, a heated sweating room. Two apodyteria, or changing rooms, two unctoria, used for oiling and bodily treatments, and two tepidaria, or warm rooms, flanked this sequence. The paired changing rooms on the eastern side served as entrances and exits and faced the nearby road.
The hot pool inside the caldarium was octagonal, approximately 7.30 metres across and one metre deep. The cold pool had an apse and was lined on its floor and walls with limestone slabs laid over a waterproof layer of tile mortar. The highest surviving walls, reaching about 12 metres, belong to a southwestern group comprising a tepidarium, an unctorium, and the sudatorium. Wall bases and trenches left by the recovery of foundations allow the rest of the plan to be reconstructed.
Heating and service areas
Furnaces and heated rooms
The western side contained the service and maintenance area. Firewood was brought into this zone and supplied to the praefurnia, the furnaces that heated the complex, where it may also have been stored. Three furnaces adjoining the sudatorium supplied heat to that room, the caldarium, and the hot pool. A hypocaust, an underfloor heating system, distributed hot air beneath the floors, while hollow terracotta tubuli in the walls carried heated air away.
The natural ground was lowest west of the building. The builders used this slope to install the heated rooms above a service basement about 1.25 metres high without extensive excavation. High openings in the walls provided access to the roof, and one passage shown in Cevet’s drawings was later blocked. The rooms were interconnected, apart from the caldarium and frigidarium, a design that reduced heat loss. The duplicated rooms also allowed the complex to adjust its operating capacity and maintain parts of the building while other areas remained in use.
Building materials and surfaces
The outer walls were about 1.20 metres thick, or four Roman feet, while the caldarium walls approached two metres. The walls used rubble enclosed between two regular faces of small limestone blocks laid in horizontal courses, a technique known as opus vittatum. The blocks measured roughly 12 by 12 centimetres, and larger limestone pieces strengthened the corners.
Terracotta building material formed the arches over doors and other openings, reinforcing them while adding a visual contrast with the limestone. It was also used alone in the lower parts of the sudatorium near the furnaces and in the hot pool. The wall construction does not use alternating brick courses, or opus mixtum, a technique that became more widespread during the second century. Exterior decoration relied on the contrast between stone and brick around the openings, together with projections and recesses that created changes in depth and shadow. Limestone survives as the lining of the cold pool, while the wider interior decorative scheme remains uncertain.
Water supply and drainage
Aqueduct and inlet
The water supply probably began at the Fontaine du Bus, also called the Fontaine du Bû, a spring east of the baths near Alauna’s ancient theatre. The spring stood at an altitude of 57 metres and was associated with an artificial regulating and retention pond. An aqueduct about 800 metres long descended 19 metres toward the baths.
Most of the aqueduct ran underground before becoming open near the complex. Seventeenth-century investigations recorded inspection shafts and a conduit about 40 centimetres wide, covered with tiles. The channel reached the southern wall of the tepidarium, followed a groove along the wall, and entered the baths through the sudatorium. Near the entrance it probably consisted of a lead pipe supported by masonry pillars or wooden posts.
Pools and drainage channels
A northern gutter carried water from the cold pool downhill toward the Merderet. Because it ran around the outside of the apsidal wall, it probably also collected some water from the roof. A separate drain for the hot pool was recorded during the 1695 excavations and shown on historical plans. The eighteenth-century demolition destroyed that drain together with the pool.
Surrounding structures
Ground-penetrating radar in 2020 detected anomalies north of the settlement that may represent channels, covered or tubular pipelines, cisterns, or reservoirs. Their connection with the water system of Alauna or the baths remains uncertain. They may instead relate to land prepared for an urban extension that was never built.
Northeastern courtyard building
A structure covering approximately 1,200 square metres was partly detected immediately northeast of the baths. It appears to include a courtyard surrounded by a colonnade, known as a peristyle, and may have been a palaestra, an exercise courtyard often associated with Roman baths. No palaestra has otherwise been identified at Alauna, so the building’s function remains provisional.
Building beside the principal road
A partitioned building between the baths and the cardo maximus may have formed part of the bath complex. Its rooms had varied possible functions, including use as a gymnasium. The structure was aligned with the road rather than with the baths, however, and may instead have been a mansio, a roadside establishment serving official travelers and others at the northern entrance to the city.
