Grotte Santo Stefano is a village in the municipality of Viterbo. It is located about 16 km from the capital of alta Tuscia, along the teverina road, towards the Tiber Valley. It is served by the station of the Viterbo-Attigliano railway.
Until January 2, 1927 it was a municipality in the province of Rome. With the reform of the provinces implemented by Benito Mussolini, starting from the following year it was aggregated to Viterbo together with the territories of Bagnaia, San Martino Al Cimino and later (from 1946, D. L. Of The Provisional head of State 20 September 1946 n. 287) Roccalvecce.
At the time, in dispute with Viterbo for the elevation to the rank of province was Civitavecchia that lost the opportunity, precisely because Viterbo managed with the aggregations of other municipalities to increase its territory and the number of inhabitants.
The inhabitants in 1974 and 1985 tried to reconstitute the autonomous municipality, but the attempts did not have the desired results and, although remaining 16 km away from Viterbo and with a population of about 3,800 inhabitants with different origins and traditions, Grotte Santo Stefano remains practically a "decentralized District" of Viterbo.