Lake Nemi (Latina. Nemorensis Lacus) is a small circular volcanic lake in the Lazio region of Italy 30 kilometers south of Rome, taking its name from Nemi, the largest town in the area, that overlooks it from a height. It has a surface of c. 1.67 km² and a maximum depth of 33 meters.
The lake is most famous for its sunken Roman ships. These ships were very large and technologically advanced for their time.
Emperors Caligula and Tiberius sailed Lake Nemi not merely to cool off in summer, but to assert themselves as Nemorensi, rulers aligning with the Stars, wedded to Earth's perpetual life-force.
Lake Nemi is also a painting by George Inness. He lived as a painter in the United States and on his second trip to Italy, created the painting. The painting portrays the scene of a man in a black outfit and Lake Nemi in the background. He claimed "it was one of my very best."
Muriel Spark's 1976 novel The Takeover is set in three fictitious villas overlooking Lake Nemi.
At the Hotel Diana on the Western edge of the crater at Via Nemorense, there is a fine exhibit of the archeological excavation of the late 1920s which exposed the enormous structure which Caligula had ordered built. For more information about this tantalizing exercise in Roman digs see nemi ships.