Viterbo Geography

Viterbo sits at about 330 metres in the volcanic belt of northern Lazio, between the Monti Cimini to the east and the Monti Volsini to the north. The whole landscape here is the product of extinct volcanoes: Lake Vico and Lake Bolsena both fill craters, and Bolsena is the largest volcanic lake in Europe.

That geology supplies the city’s two defining materials. Peperino, a grey welded tuff, is quarried locally and is what almost every building in the old town is made of. And the same volcanic system heats groundwater, which surfaces west of the city as sulphurous springs at around fifty-eight degrees.

The surrounding Tuscia is a plateau of soft tufa cut by deep, wooded gorges. Etruscan towns were built on the flat-topped spurs between them, and their tombs were cut into the gorge walls — which is why the countryside here holds necropolises rather than ruins.

The Monti Cimini above the city are covered in beech and in hazel plantations, and are noticeably cooler than the plain.