Statistics for occurrence #1 of “Umbria” in book 2, chapter 7, section 1 of Vitruvius Pollio, The Ten Books on Architecture:

...i, at Amiternum, or Mt. Soracte, and in quarries of this sort; in still others it is hard, as in lava quarries. There are also numerous other kinds: for instance, in Campania, red and black tufas; in Umbria , Picenum, and Venetia, white tufa which can be cut with a toothed saw, like wood.
Max. Freq. Min. Freq.
Entity Corpus Doc Corpus Doc  
Umbria (Italy) 46 2 0 0 0 user votes
Umbria (Ohio, United States) 4 0 0 0 0 user votes

† This entity has been selected by the automated classifier as the most likely match in this context. It may or may not be the correct match.