a history of nearly 2,000 years!
Just twenty kilometres from Avignon, in the direction of Uzès, is a remnant of the Roman Empire: the Pont du Gard, a must-see site in the region.
This nearly 2,000-year-old monument, preserved in exceptional state, is a Unesco World Heritage Site. It is part of the aqueduct linking a spring near Uzès to the city of Nîmes.
The Gallo-Roman Forum of Nemausus by Ferdinand Perthus (1883-1948)
Reconstruction of the Thermes de Lutèce and the Hôtel de Cluny (Watercolour by Camille Bernard 1914)
Water, an essential element of the Roman art of living
In the 1st century AD, the Gallo-Roman city of Nemausus (today Nîmes) with its 20,000 inhabitants was one of the most important cities of the Provincia Romana on the main communication axis between Lugdunum (Lyon) and Rome.
Following the example of Rome, which was the model for the entire Roman Empire, the inhabitants adopted Roman customs and enjoyed the benefits of pressurised water to make everyday life easier. The wealthiest had running water directly from the fountains in their atrium (the inner courtyard of private villas). The less well-off come to fetch water from the many public fountains placed at street crossings and in squares.
The Romans did not linger at home for the toilet, but regularly went to the public baths and spas, which were accessible to all, to wash themselves but also to spend whole afternoons meeting friends, doing business, cultivating themselves or playing sports. The water from the aqueduct was also used to fight fires, which were frequent at that time, and to sanitise the city by draining the sewage system and the latrines (public toilets where water circulated permanently under the seat). The naumachies (naval battles) were held in Nîmes as in Rome, flooding the amphitheatre’s arenas. Water also had to be supplied to the craftsmen (laundress, fuller, potters, masons, etc.) for their activities.
To satisfy all these needs, the Romans needed clear water whose flow did not vary from one season to another. The water of the Rhône being too turbid, the Gard and the Gardon being dry in the summer and flooding in the winter, it was necessary to find a spring nearby with a large enough flow. Moreover, as Nîmes is at an altitude of 194 feet, these rivers were much too low. In order to supply the city, it was necessary to capture the water higher up so that it could flow to Nîmes by gravity. Only one spring met all the criteria, the Eure spring near Ucetia (Uzès) located at an altitude of 236 feet.
An aqueduct with a cleverly designed route by the Roman engineers
Between this spring and Nîmes, there were only 12.5 miles as the crow flies, but an obstacle stood between the two: the Nîmes garrigue massif, culminating at an altitude of more than 650 feet. At that time, it would have been impossible to dig a tunnel because the rock at that point was much too hard. The Romans therefore decided to bypass the obstacle by means of an aqueduct on a 31 miles diversions along a Roman road. This certainly simplified the transport of men and equipment, but the engineers had to calculate the slope as accurately as possible all along the route, since there is only a 42-feet difference in height between the spring and Nîmes.
Canal of the 3rd level of the Pont du Gard where water circulated.
The construction of the aqueduct
The construction of the aqueduct began between 40 and 60 AD during the reign of the emperors Claudius and Nero. The work lasted from 10 to 15 years, including 5 years for the sole Pont du Gard.
The water from the Eure spring is directed towards a regulation basin near Uzès where its flow was regulated manually with a wooden valve system. The water then flowed into a vaulted canal forming most of the underground route, but arched bridges and culverts had to be built to cross the valleys and keep the slope perfectly constant. The Pont du Gard is the most spectacular piece of this aqueduct. It is the highest aqueduct bridge ever built by the Romans: 160 feet high.
The choice of the site was not random
The architects in charge of the project had to take into account the problem of crossing the Gardon and it was at the precise point of maximum narrowing of the gorge that the bridge was placed. On either side of the valley, the emergence of limestone rocks to lay the foundations of the building was a factor of stability and on the left bank, the relatively less steep northern slope made it possible to easily supply the site.
The architects of that time designed it to resist the sometimes violent floods of the river. In fact, in order to offer the least possible resistance to the current, the main arch literally spans the bed of the Gardon over a distance of 82 feets, which is a real feat for the time. In addition, the piers were cut to a point in order to cut the current. The structure consists of 3 levels of superimposed arches: 6 arches, the widest on the first level, 11 on the second and 47 arches on the highest level supporting the canal over 900 feet.
To build the aqueduct, limestone was needed, most of it extracted from quarries near the bridge. For the Pont du Gard alone, it is estimated that around 50,000 tonnes were needed, almost five times the weight of the Eiffel Tower. Up to a thousand workers were employed on the site: quarrymen to extract the blocks of stone, transporters to move them, cutters to shape the soft limestone blocks on the spot, earthworkers to prepare the ground, masons, lumberjacks, carpenters to make the wooden arches and lifting equipment, blacksmiths to make the iron tools, and kiln workers to burn the limestone from the garrigue in order to obtain the lime…
The canal (specus) where the water circulated is the main part of the aqueduct
It is generally 4 feet wide and 6 feet high. It is vaulted and supported by two pedestals, and rests on a platform made of lime mortar. The waterproofing was ensured by a mortar based on sand, lime and tile debris, which was then covered with a waterproofing coating based on fig juice. The water flowed on a gentle slope of 16 inches per mile on average. On 90% of the route, the canal was buried and on the remaining 10%, to which the Pont du Gard belongs, it was necessary to build bridges with arches, the technique of which the Romans mastered. The arch is built on temporary wooden arches. The structure allowed a flow of 100 Gallons (Imp) or 120 Gallons (fluid-US) of water per second.
The water reception basin in Nîmes (Castellum Diversum)
At the end of the aqueduct, after passing through the tunnels of Sernhac dug with simple spikes, the water arrived in Nîmes in a basin called the Castellum Diversum (Water Castle) located on the hillside. Intended for the distribution of water in the city, it is one of the rare monuments of this type that has reached us in a remarkable state of preservation, along with that of Pompeii. From this distribution basin, water was redistributed to the different districts of the city of Nîmes through a network of lead pipes.
To build the aqueduct, it is estimated that the Gallo-Roman city had to spend around 100 million sesterces (the equivalent at the time of 45 million euros today). Its financing certainly obliged the people to pay more taxes but also rich notables of Nemausus had to make some donations and the emperor himself participated.
The aqueduct over the centuries to the present day
The aqueduct will supply the city with water for 5 centuries. Afterwards, due to lack of maintenance, the water passage was gradually blocked and the aqueduct lost its efficiency. From the 3rd century onwards, the peasants drew water from the aqueduct by tapping. The leaks caused enormous limestone concretions to form along the cultivated land. The work was abandoned and partially destroyed from the 6th century onwards. In the 12th century, many stones were looted to build houses and the Pont du Gard became a pedestrian bridge, allowing carts to cross from one bank of the Gardon to the other. A road bridge adjoining the bridge, known as the Pitot bridge (named after its designer, the Aramon engineer Henri Pitot), was built in the 18th century. After its inscription on the Unesco World Heritage list in 1985, the site was developed to welcome the increasing number of visitors.
Today the Pont du Gard is the only example of an ancient three-storey bridge in an exceptional state of preservation and one of the most visited monuments in France with no less than 1.5 million visitors each year.
A whole day should be devoted to fully enjoy the visit. The entrance fee includes access to the site but also a visit to the Museum which should not be missed. It is the largest interpretation centre in France on Roman multidisciplinary engineering and tells the story of the Nîmes aqueduct with models, full-scale reconstructions, virtual tours, interactive screens, sound effects, a cinema with a giant screen showing an educational documentary using computer-generated images to understand the technical challenge that the construction of the bridge represented for the engineers of Roman antiquity.
A breathtaking panorama
Outside, you can discover the whole site through a walk in the garrigue overlooking the bridge and admire the views. From this hill, the panorama is magical and you can take a more complete guided tour by accessing the inside of the canal (different schedules are offered in summer). A walk on the first level allows you to observe the small boats and canoes passing underneath. Swimming on the banks is permitted but not supervised and bathers are welcome to cool off in the Gardon. It is possible to picnic on site.
The site visit
The entrance ticket also includes parking at the site’s car park. It should be noted that it is extremely difficult, if not impossible, to park in the vicinity. A good alternative to the car for non-vehicular visitors is the bus from Avignon, as the site is easily accessible on foot from the bus stop. The journey takes about 30 minutes.
Another tip is to buy the ticket on the Internet, as it is cheaper than the ticket office on site and allows you to get through a fast queue.