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WonderRoman engineering fact

The Pont du Gard in southern France is a three-tier Roman bridge, 48.8 metres high, built to carry the aqueduct that supplied Nîmes across the Gardon River while keeping the very slight downhill slope that let water flow by gravity alone.

Roman Gaul, 1st century AD

EngineeringArchitectureHistoryTechnology

The story behind the card

The aqueduct ran about 50 kilometres from a spring near Uzès to Nîmes, yet dropped only about 12.6 metres over its whole length, an average of some 25 centimetres per kilometre. The bridge's lower arches span the river, and a row of small arches on top carries the covered water channel. It is the tallest Roman aqueduct bridge still standing. Most historians date it to the first century AD, possibly the reign of Claudius. After the aqueduct fell out of use, around the sixth century, the bridge served for centuries as a road crossing, and parts of its second tier were cut away to let carts through. Napoleon III ordered a major restoration in the 1850s, and UNESCO listed it as a World Heritage Site in 1985.

Türkçe oku
Güney Fransa'daki Pont du Gard, 48,8 metre yüksekliğinde, üç katlı bir Roma köprüsüdür. Nîmes kentine su taşıyan kanalı Gardon Nehri'nin üzerinden geçirmek için yapıldı ve suyun yalnızca yerçekimiyle akabilmesi için gereken çok hafif eğimi korur.
Roma Galyası, MS 1. yüzyıl

Su kanalı Uzès yakınlarındaki bir kaynaktan Nîmes'e kadar yaklaşık 50 kilometre uzanıyordu; buna karşın bütün yol boyunca yalnızca 12,6 metre kadar alçalıyordu. Bu, kilometre başına ortalama 25 santimetre demektir. Köprünün alt kemerleri nehrin üzerinden geçer, en üstteki küçük kemer dizisi de üstü kapalı su kanalını taşır. Ayakta kalan en yüksek Roma su kemeri köprüsüdür. Tarihçilerin çoğu onu MS 1. yüzyıla, belki de İmparator Claudius dönemine tarihlendirir. Su kanalı 6. yüzyıl dolaylarında kullanılmaz hâle gelince köprü yüzyıllarca yol geçidi olarak kullanıldı; arabalar geçebilsin diye ikinci katın ayaklarının bir kısmı oyuldu. III. Napolyon 1850'lerde kapsamlı bir onarım yaptırdı; UNESCO köprüyü 1985'te Dünya Mirası Listesi'ne aldı.

Sources and further reading

Background reading: Pont du Gard
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