Ancient Roman defensive walls

City walls were already significant in Etruscan architecture, and in the struggle for control of Italy under the early Republic many more were built, using different techniques.

Later the Aurelian Wall replaced it, enclosing an expanded city, and using more sophisticated designs, with small forts at intervals.

The Romans walled major cities and towns in areas they saw as vulnerable, and parts of many walls remain incorporated in later defences, as at Córdoba (2nd century BC), Chester (earth and wood in the 70s AD, stone from c. 100), and York (from 70s AD).

Most defences of the borders of the Roman Empire relied on systems of forts and roads without attempting a continuous barrier.

Notable walls built by ancient Rome include, in chronological order of construction:

Section of the Servian Wall
Section of the Roman walls of Lugo , Spain, 263–276 AD
The Porta Nigra of Trier , Germany , capital of the Roman province of Gallia Belgica , constructed between 186 and 200 AD.
Diocletianopolis city walls, Hisarya , Bulgaria