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At the Pont du Gard

1 - 2,000 years ago, the Roman Empire stretched around the Mediterranean. What is now France, which the Romans called Gaul, was also part of it. In the south of Gaul lay the city of Nemausus, now called Nîmes. At the time, around 20,000 to 25,000 people lived there.

2 - Some structures from this period have survived, including the amphitheatre, the “Great Tower” as part of the city wall, the Augustus Gate and a temple dedicated to the goddess Diana. These works by Roman builders have stood for two thousand years.

3 - About 20 kilometres northeast of the city is a particularly impressive example of Roman engineering: the "Pont du Gard". It is the bridge over the River Gardon, which was called Vardo in Roman times. It was part of an aqueduct, a stone water channel that supplied the city of Nîmes with water, which was essential for life.

4 - The aqueduct was about 50 kilometres long in total. The water came from springs near the town of Uceta, now called Uzès. The difference in elevation between the start and end of the aqueduct was only 12 metres, or 24 centimetres per kilometre. Parts of the aqueduct ran through tunnels that had to be dug into the mountains. The mountainous terrain meant that many detours were necessary.

5 - Nevertheless, the builders managed to maintain a steady, gentle gradient. They did their calculations without calculators or computers. Crossing the valley carved out by the River Gardon presented the builders with particular challenges. They eventually built a bridge that was 49 metres high and had 3 rows of arches, one above the other.

6 - The lower level consisted of 6 arches. It is 22 metres high, 6 metres wide and 142 metres long. The 11 arches on the middle level are closer together. They span a length of 242 metres, are 4 metres wide and 20 metres high. The third level has 35 arches. It is 275 metres long, 3 metres wide and 7 metres high.

7 - Above the third level, the builders constructed a stone channel. It was only 1.80 metres high and 1.20 metres wide. About 20 million litres of water flowed through this channel every day. Each resident of Nemausus therefore used an average of about 1,000 litres per day.

8 - The water was of excellent quality. But it was not used only as drinking water. The Romans liked to spend the day in bathhouses, where there was plenty of water. In any case, they used much more water than we do today. 

9 - Large rectangular stones from nearby quarries were used to build the Pont du Gard. Their edges were cut so evenly that they could be stacked without mortar.10 - It is estimated that about 1,000 workers spent three years building this great structure. They worked with simple tools. The stones were lifted into place using construction cranes powered by treadwheels. In some places, uneven stones protrude from the walls; these were probably used to anchor the scaffolding. 11 - For several centuries, the aqueduct supplied the city of Nemausus with water. But it was eventually no longer properly maintained. By the 8th century, it had fallen into disuse. People began removing individual stones from the structure and using them in other buildings.

12 - The lower level of the Pont du Gard was later used as a road bridge. Since 1985, the Pont du Gard has been specially protected as part of the UNESCO World Heritage Site. Many tourists visit the structure every year and marvel at what people could achieve as long as 2,000 years ago.