Slope Instabilities and Restauration in the Historical Town of Orvieto

Abstract

Orvieto is superbly situated on the top of a volcanic outcrop (Fig. 7.1), whose precipitous walls encircle Orvieto like a fortress. Orvieto’s singular geographical positioning has made it a naturally fortified city. It has consequently never had to be surrounded by man made fortified walls. It dominates the broad valley of the river Paglia, a tributary of the Tiber. The tuff outcrop, on whose plateau Orvieto sits, rises like an island in the broad and level Paglia valley. Modern Orvieto is surrounded by an extensive agricultural region.