The Pont du Gard is nearly fifty metres high and visible from far off, and that is why everyone goes. It is also why almost nobody looks at the thing that makes it a masterpiece, because that part cannot be seen at all.
The bridge is not a bridge. It is the stretch where an aqueduct had to cross a valley, and it is the only piece that had to be built high. The rest, some fifty kilometres of it, runs underground or at ground level, and nobody photographs that.
What was there to solve, if water runs downhill by itself?
Fifty kilometres to fall twelve metres
The water started at the Fontaine d’Eure, near Uzès, and had to reach Nîmes, Roman Nemausus, where a distribution basin sent it on to the fountains, the baths and the houses. As the crow flies that is under twenty kilometres. The route covers about fifty, because it has to work round the high ground while never stopping going down.
And here is the real problem. Over the whole run the total fall is a little over twelve metres, which is less than twenty-five centimetres per kilometre. Some sources give a larger figure, around seventeen metres; what they all agree on is the order of magnitude, and the order of magnitude is what matters. A gradient that small has to be held constant for fifty kilometres with levelling instruments that sit on a tripod.
On the Pont du Gard itself, whose upper tier measures a little under three hundred metres, the channel falls by about two and a half centimetres. Over that length it is a line the naked eye reads as horizontal. Err by a few centimetres too much and the water speeds up and wears the channel away; err the other way and it stops and stagnates. The monument you are looking at is the easy part of the job.
How it is built
The bridge has three superimposed tiers of arches, and the count runs like this: six arches at the bottom, eleven in the middle, thirty-five at the top. The upper level originally had forty-seven, and the difference has fallen away over the centuries.
The three tiers differ for a structural reason. The lower arches are few and very wide because they have to span the river and carry the whole load; going up they become more numerous and narrower, and the structure lightens as the weight it has to carry decreases. At the top, above the last row, runs the covered channel the water passed through, a little over a metre wide.
The stone comes from a quarry a few hundred metres away, a local limestone that time has turned yellow and gold. The largest blocks weigh several tonnes and in the lower part are laid dry, without mortar: the structure holds by weight and by friction, not by adhesion.
It was built in the 1st century AD, and it has been on the UNESCO World Heritage list since 1985.
The stones that stick out, and why nobody removed them
As you get close to the piers you will notice stone corbels projecting from the blocks at regular intervals, all the way up. They look like damage or like unfinished work, and they are the most instructive thing about the monument.
They are the supports for the scaffolding. The builders cut them from the blocks themselves instead of raising a scaffold from the ground, which at that height and over a river would have been a second building site. When the work was done they did not cut them off, and the reason is practical: an aqueduct needs maintenance, and those supports let you put the scaffolding back whenever it is needed.
Look at them, because they say something monuments usually hide: here the method of construction has stayed in plain sight, and the people who built it saw no need to erase it.
The eighteenth-century road bridge alongside the Roman one
Looking at the monument from downstream you notice that the lower tier is wider than the others and carries a flat roadway. That part is not Roman.
Between 1743 and 1747, to a design by the engineer Henri Pitot, a road bridge was built against the flank of the lower arches, to carry carriages where people had previously forded the river. It is the reason you now cross the Gardon walking beside the monument rather than under it.
Strictly speaking it is an addition that alters the monument, and there are good grounds for calling it the monument’s salvation too: a useless ruin gets dismantled for its stone, a working bridge does not. The Pont du Gard came through the modern age because it was good for something.
Why it stopped working
The aqueduct was not destroyed: it silted up.
The water of the Fontaine d’Eure is very hard, and passing along the channel it laid calcium carbonate on the walls. Over the centuries that deposit grew until it reduced the cross-section, and in places the layer is tens of centimetres thick. The concretions are still visible in the channel.
After the 3rd century maintenance thinned out, and the flow with it. The aqueduct stayed in partial use for a long while, then it was abandoned and its stones served as a quarry for the surrounding country. The bridge survived because it was too useful as a crossing.
One curiosity: the limestone deposit is not only a fault. It is also an archive, because it built up in seasonal layers like the rings of a tree, and studying it has established for how many years the water actually ran.
The river, which is half the visit
There is something the historical guides leave out and the photograph makes obvious at once: people swim under the bridge.
The Gardon runs through a gorge of white rock, with green water and deep pools, and in summer its banks are a river beach. People swim, take canoes out, lie on the stone slabs. It is a use of the monument that jars with the archaeological-site tone, and it is, to my mind, the right way to spend a day here: arrive in the morning, look at the bridge, get in the water and look at it again in the late afternoon light, which suits it best.
Take note: the Gardon is a Mediterranean river, so in summer it is low and placid but in autumn it can rise fast. Bathing conditions are signposted on site and should be read rather than inferred from the fact that other people are in the water.
Practical information
Data checked on 8 August 2026 on the official site pontdugard.fr. Prices, hours and the events calendar change: check again before you travel.
Seeing the bridge costs nothing. The site states that access is free and open, and that you pay only for parking and for guided tours. It is the most useful piece of information on this page and almost nobody writes it down. Parking. It costs 9 euros per vehicle, whatever the number of people and however long you stay. Arrive on foot or by bicycle and you pay nothing. The museum spaces. The museum, the cinema, the games room and the temporary exhibition cost 8 euros for adults and 6 euros for the unemployed. They are free for under-18s, for students on the family option and for visitors with disabilities. Guided tours and audio guide. A guided tour costs 15 euros for adults, 13 reduced and 6 euros for children aged 4 to 17. The audio guide costs 4 euros per person. Site hours. In January, February, November and December it opens 9.00-17.00. In March and October it opens 9.00-18.00. From April to June and in September it opens 9.00-19.00. In July and August it opens 9.00-20.00. In summer you come back in the evening. From 15 May to 20 September 2026 the monument is lit every evening at dusk, and from 4 July to 30 August 2026 there is a sound and light show at 22.30 lasting about twenty minutes. These dates come from the calendar circulated by the site and by the tourist bodies of the Gard: confirm them before planning the evening. The exhibition of summer 2026. From 29 May to 1 November 2026 there is an exhibition devoted to Robert Combas, with around forty works on antiquity and mythology. Getting there. The site has two entrances, right bank and left bank, with over 1,400 parking spaces between them. From Nîmes and from Uzès it is under thirty kilometres, from Avignon a little more. How long it takes. Two hours are enough for the bridge and the museum. With a swim in the Gardon it is a day. What time to go. Late afternoon, when the stone turns from yellow to orange and the raking sun picks out every single block. At midday in summer the light is overhead, the limestone is white and flat, and there is no shade anywhere.
The Pont du Gard makes more sense seen together with the place the water was going: what to see in Nîmes covers the city that aqueduct supplied, and the arena of Nîmes is the best preserved Roman amphitheatre in the world. If your journey carries on towards the Pyrenees, Carcassonne and Collioure are the next stops.
