Aqua Marcia
The south side of the Marcia bridge crossing the Via Empolitana, 3 km SE of Tivoli, after
the Marcia crossed the Fosse degli Arci, a tributary of the Anio river. The opening left is
part of the channel of the Anio Vetus. The core of the bridge is made of concrete faced with
blocks of cut stone (opus quadratum).