FERENTUM or FERENTIS, an ancient town of Etruria, about 6 m. N. of Viterbo and 31 m. E. of the Via Cassia. It was the birthplace (A.D. 32) of the emperor Salvius Otho, was de stroyed in the 11th century, and is now entirely deserted. It occupied a ridge running from east to west, with deep ravines on three sides. There are some remains of the city walls, and of various Roman structures, including some baths, of which the most important is the theatre. The stage front is still standing; it is pierced by seven openings with flat arches. It has recently been well restored, and fitted for use for theatrical representation. The necropolis was on the hill called Talone on the north-east. A tomb of the Republican period with several sarcophagi of the gens Salvia, no doubt ancestors of the emperor Otho, has been found there.