The main channel runs directly from the tunnel. Branching off to the left is the escape channel. Water was regulated by sluice gates dropped in to grooves cut in the stone at the entrace to each channel, visible on the left, just beneath the point where the arch meets the foundation.
Looking back from the regulation basin along the channel of the aqueduct in la vallée de l’Eure, Uzès.
There is little evidence of concretion in the early stages of the aqueduct. The chemical reaction between air and water that crystalized the calcium took about 10 hours. Close to the source, there was insufficient time for the sediment to be deposited.
At ground level, the channel is dug out of the limestone hillside on the left. On the right, the form of construction shows the dimensions of the channel, 1.2m wide at the base and tall enough for a man to walk through it.
Approaching the first of the bridges on the route from Uzes to le pont du Gard, bathed in spring sunlight, it offers a bucolic vision, bringing to mind haystacks and swains rather than centurions and stonemasons.
at modern ground level you see the arches which supported the channel, now deeply rutted by centuries of farm use.
This is the only one of three original arches that remains open. You can clearly see the unique structural design of this bridge: each span was formed of an arch built with a single width of cut stone. all the others on the route, and typically in Roman design, would have used multiple sets of interlocking stone across the width of the bridge.
The view from upsteam, showing the powerful triangular cutwater on the left of the channel, designed to break the force of the water.
Crossing a farm track near le pont de Bornègre, the line of the aqueduct is marked by a just visible line of cut stone, with the original concrete indicating the inside of the channel to the right. Less visible, but nonetheless present, 1.2m to its right, is the merest outline of concrete to confirm the presence of the channel.
Leading from Vers-Pont-du-Gard to the quarry from which much of the stone for le pont du Gard was taken. Deeply rutted over time, there is a sense of scale to these things that belies the grandeur of l’aqueduc de Nîmes.
Thrusting into empty space. This photo was taken in January 2018. On a return visit in February 2019, the long section of the fill extending beyond the remnants of the arch support had fallen.
The concretion on the underside of the cut stone arches, gives the structure an almost organic softness.
A large gobbet of concretion sitting under one of the arches of le pont de la Lône.
Looking back towards Vers. A simple wall on which the channel was built, approaching the now largely absent pont de Font-Ménestière. In the distance are the remnants of a pillar which supported the channel itself.
Impressive in its scale, le pont Roupt marks the start of the final approach to le pont du Gard.
Continuing its march towards le Gardon, showing some of the stonework added to safeguard the remains.
A well-sited tree having taken root completes the scene.
The channel sits on top of an imposing structure, 49.4 metres above le Gardon.
In dramatic winter sun, from the rive droite, looking back to the point of entry of the water into the channel.
The channel as it arrives at the end of its crossing of le Gardon.
Having crossed le Gardon, the aqueduct begins a long and serpentine wander through the woods of Remoulin, skirting les garrigues de Nîmes, and entering the most dramatic part of its route.
The first of the bridges supporting the channel in les bois de Remoulins.
Cookie the Aquedog overlooking le pont Valmale - or where it was.
The camera was perfectly vertical - really! The path alongside the acqeduct en route from le pont Valmale to le pont de la combe Roussière.
A dramatic void hints at what was once the largest and most impressive of the bridges in the valleys of les bois de Remoulins.
The first of the bridges which can be crossed on foot. At its far end it shows clearly the effects of concretion, with the channel eventually reduced to a mere 33cm from an original 1.2m.
Looking down from the garrigues.
The bridges sit nestled down in the valley, in stark contrast to le pont de la Lône and le pont Roupt, standing as they do on their superstructure, built on level ground. This produces an almost tromp l’oeil effect, playing tricks with the perception of relative elevation. The total drop over 50km remains a mere 12m!
Valley four and counting…. A good view of concretion on the right side, where the flow would have been strongest turning into the bridge.
While the bridge can only be approached from the valley, there being no viable route following the line of the acqueduct from le Ponceau, it is possible to walk several hundred metres back towards le Ponceau, from where this view opens up.
The view upstream
Another odd structure: arches within arches, with the actual water channel nothing more than a culvert.
Heavily overgrown, difficult to access and difficult to interpret the platform level having made it there, there remains nevertheless yet another unique design to be enjoed: a small arch in the shape of an inverted hear graces the last of the bridges in les bois de Remoulins.
This is a gallery of black and white impressions of l’aqueduc de Nîmes - except that, when confronted by the subtlety of light and colour in les tunnells de Sarnhac, the exceptions to the rule emerge. This and the next image capture this otherworldly sense.