Rome boasts the longest set of city walls in the world, most of which are still standing. The walls were built on the orders of the emperor Aurelian (r. 270-75), who died shortly before they were completed.
Constructed out of brick-faced concrete, they are 3.5 m (12 feet) thick and originally ran for 19 km (12 miles). The walls were punctuated by 380 towers, at intervals of 100 Roman feet (29.6 m), and 18 gates. Originally 8 m (26 ft) high, the height of the walls was later doubled to 16 m (52 ft).
The Aurelian Walls, which remain remarkably well-preserved, superseded the Servian Wall, which had been built in the early 4th century BCE. The Servian wall was 10 m (33 ft) high in places, 3.6 m (12 ft) wide at its base and 11 km (6.8 miles) long. It is believed to have had 16 main gates.
Only a few short stretches of the Servian wall, which was built out of large blocks of tuff quarried from the Grotta Oscura quarry near Veii, remain.
My name is David Lown and I am an art historian from Cambridge, England. Since 2001 I have lived in Italy, where I run private walking tours of Rome.
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