Aqueduct of Claudia, Compagna. Aqua Claudia was an ancient Roman aqueduct that, like the Aqua Anio Novus, was begun by Emperor Caligula (37–41 AD) in 38 AD and finished by Emperor Claudius (41–54 AD) in 52 AD. It was the eighth aqueduct to supply Rome, and it is regarded as one of the "four great aqueducts of Rome". Its mainsprings, the Caeruleus and Curtius, were situated 300 paces to the left of the 38th milestone of the Via Sublacensis. The total length was approximately 69 kilometres (43 mi), most of which was underground. Nero extended the aqueduct with the Arcus Neroniani to the Caelian hill and Domitian further extended it to the Palatine, after which the Aqua Claudia could provide all 14 Roman districts with water. Very good contrast and tonality. 10 x 14.25 in. 25.5 x 36 cm. Photograph is larger than scanner part does not show.