Orvieto

Orvieto is a city and comune in Province of Terni, southwestern Umbria, Italy situated on the flat summit of a large butte of volcanic tuff. The site of the city is among the most dramatic in Europe, rising above the almost-vertical faces of tuff cliffs that are completed by defensive walls built of the same stone called Tufa.

Read more about Orvieto:  Economy, Twin Towns - Sister Cities