The Museum of Roman Ships of Nemi, was built between 1933 and 1939 to house two gigantic ships that belonged to the emperor Caligula (37-41 AD) recovered in the waters of the lake between 1929 and 1931. It was therefore the first Museum in Italy to be built according to the content, two hulls measuring respectively m. 71.30 x 20 and m. 73 x 24, unfortunately destroyed during a fire in 1944. In the new layout of the Museum of Roman Ships, the left wing is dedicated to the ships, of which some materials that survived the fire are exhibited, the reconstruction of the roof with bronze tiles, two anchors, the lining of the bow wheel, some original or reconstructed on-board equipment. Also visible are two scale models of Caligula's ships and the life-size reconstruction of part of the stern of the first ship. The right wing is instead dedicated to the settlement of the Albanian territory in the republican and imperial age, with particular regard to places of worship; there are votive materials from Velletri (S. Clemente), from Campoverde (Latina) from Genzano (stipe di Pantanacci) and from the Sanctuary of Diana in Nemi, as well as materials from the Ruspoli Collection. Inside this wing of the Museum it is also possible to admire a stretch of the ancient Roman road, the clivus Virbii, which led from Ariccia to the Sanctuary of Diana.