a city and comune in the Province of Terni, southwestern Umbria, Italy situated on the flat summit of a large butte of volcanic tuff. The city rises dramatically above the almost-vertical faces of tuff cliffs that are completed by defensive walls built of the same stone called Tufa.
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[...] it seemed like such an abhorrent extravagance to fly Mudd all the way across the ocean just to have him blown into bits over Orvieto less than two hours after he arrived.