BOLSENA, a town of Italy, in the province of Rome, and the district of Viterbo, 10 miles S. by E. of Orvieto. It is situated on the north shore of the lake of the same name (Lago di Bolsena), and probably occupies the site of the Roman city of Volsinii. The principal remains are the ruins of an amphitheatre and those of a temple, which is popularly called il Tempio di Norzia after the Etruscan goddess Norsia, and there are numerous other relics scattered throughout the city or built into the walls of its modern buildings. Volsinii was originally one of the most powerful of the Etruscan cities, and occupied a position among the hills; but after a series of struggles with the Romans, the Volsinians were finally subdued about 280 b.c., their city was razed to the ground, and themselves obliged to settle in a less defensible site in the plaiu. The only event of interest in the history of the new town was its being the birthplace of Sejanus, the favourite of Tiberius. Its present population is only 2690. The Lake of Bolsena is about 10 miles in length by 8 in breadth, and is surrounded by well-wooded hills. It contains two small islands, Bisentina and Martana, iu the latter of which Amalasontha, the wife of Theodatus, king of the Goths, was put to death by his orders.