Lago di Bolsena

Lake Bolsena (Italian: Lago di Bolsena) is a crater lake of central Italy, of volcanic origin, which was formed 370,000 years ago following the collapse of a caldera of the Vulsini volcanic complex [1]. Roman historic records indicate activity of the Vulsini volcano occurred as recently as 104 BC, since when it has been dormant. The two islands in the southern part of the lake have been formed by underwater eruptions following the initial collapse of the caldera.
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