The Cloaca Maxima at Rome
In these Etruscan buildings traces are to be found of the arch; as, for instance, in the Gate of Volterra and other gates at Perugia; so also in the Cloacæ at Rome, of which the Cloaca Maxima is 20 feet broad. These are sewers which were intended to render the marshy district between the hills of Rome inhabitable. They were constructed in the reign of Tarquinius Superbus, at the beginning of the sixth century B.C.
A. Rosengarten, W. Collett-Sandars A Handbook of Architectural Styles (New York, NY: Charles Scribner's Sons, 1895)
Courtesy the private collection of Roy Winkelman