11. Defending the Roman city: Barcino’s walls
By the end of the 3rd century, the danger posed by the incursions of the Franks into Hispania Tarraconensis province prompted Barcino to revamp its original city walls by reinforcing their facings and equipping them with seventy-seven towers. The funerary monuments running around the walls were plundered for building material to enhance the defences.
The construction work turned the small centre of the city into a fortress which was easy to defend. This added to its strategic value and meant various authorities chose it as a seat of power in the Visigothic and Carolingian periods.