How Tuscania was built and evolved over time

Tuscania was built on tufa, in several places at once, and moved.

The site is seven tufa promontories between the river Marta and the Fosso Capecchio — soft volcanic rock that can be cut as easily as it can be built on, which is why the territory holds twelve distinct rock-cut necropoleis.

The first urban act was the acropolis. From the eighth century BC the hill of San Pietro was urbanised, and by the seventh century, in the English account, it had been surrounded by a line of walls.

Then the centre moved. That acropolis now lies outside the city's walls, which means the medieval and modern town occupies different promontories from the Etruscan one — a shift of centre within a single site.

The walls a visitor sees are imperial and dated. Frederick II of Hohenstaufen captured the city on 2 March 1240 and provided it with a line of walls.

And the economy that paid for the building was agricultural and commercial: farming on the valley, the port of Regas on the coast, and the Via Clodia running through.