A key element in Roman pacification of Gaul was largesse. Colonia Nemausus (Nȋmes) the ex-capital of the Celtic Volcae that was occupied by the Romans c. 42 BCE, is a prime example. Under Emperor Augustus, it was endowed with city walls punctuated by 14 watchtowers, an amphitheatre, temple and grand civic buildings and, most strikingly, the aqueduct. An astonishing feat of engineering, the aqueduct extends 15.6 miles (25 km) from its origin, the springs at Uzès, with a gradient of just 0.03 per cent. En route the Pont du Gard bridges the gorge of the Gardon River, spanning 984 ft (300 m), and reaching a height ot 164 ft (50 m). For good measure, it then circumvents a lake on its tortuous passage to the Colonia, through heavily wooded hills, requiring tunnels – the longest around Sernhac, 1,312 ft. (400 m) long. The aqueduct was built of limestone and ashlar with concrete footings and was completed c. 19 BCE by Marcus Vipsanius Agrippa, Augustus’s industrious son-in-law.
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