The beautifully crafted bronze head of Medusa, one of the exhibits in the Palazzo Massimo alle Terme, dates back to the reign of the emperor Caligula (r. 37-41). It is almost all the survives of two huge boats that were built at the emperor's behest for Lake Nemi, which lies about 20 miles to the south of Rome.
The boats, the largest was 73 m (240 ft) long and 23 m (79 ft) wide, were, in truth, floating pleasure palaces on which Caligula, one of the most notorious of Rome's emperors, would hold wild parties.
Caligula's reign was brief and he was assassinated on January 24th, 41. Shortly after his death the boats met the same fate as their creator. Their hulls were pierced and, weighted down with heavy stones, they sank to the bottom of the lake.
There they lay for more than two thousand years until in 1929, on the orders of Italy's fascist dictator Benito Mussolini (r. 1922-43), Lake Nemi (with a surface area of 0.6 square miles and a depth of 65 feet) was drained. The remains of the two boats were found lying in the mud at the bottom of the lake.
A museum was duly built to house them. It opened in 1940, but four years later, during the night of May 31st 1944, a fire broke out and the boats were consumed in the flames. Whether the fire was caused by allied or German troops is still a matter of debate. All that survived were a few bronze artefacts (such as the head of Medusa) and the memory of one of the greatest excavations of the twentieth century.
One of the reasons that Caligula chose Lake Nemi is that it was home to a temple to the goddess Diana Nemorensis, one of the most popular shrines in the ancient world. Her temple stood on the north shore of the lake, known by poets as Speculum Dianae (Diana's Mirror), beneath the modern town.
The priest of her temple had to be a runaway slave and could only be removed from his post by another fugitive slave. A potential successor had to cut a branch from a special tree, which stood in the scared grove of Ariccia, and challenge the holder to a fight to the death.
My name is David Lown and I am an art historian from Cambridge, England. Since 2001 I have lived in Italy, where I run private walking tours of Rome.
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