The temple of the Lares Permarini. This temple, concecrated to the Lares who protect sailors, was vowed by L. Aemilius Regillus during a naval battle with the forces of Antiochus in 190 B.C., and dedicated in 179. As it is said to have stood in campo Martio and also in porticu Minucia, its location depends upon that of the porticus.
Situated approximately one-third up the one and a half mile race-course, the Naumachia Domitiani, through its massiveness and presumed height alone, is a prominent presence along the Equiria. Piranesi also positions the Naumachia Domitiani together with the Templum Castorum and the Templum Deorum Larium Parmarini, which consequently forms a group of buildings dedicated to ancient Rome's naval military forces.
The Templum Castorum sits between the Porticus a S.P.Q.R. Amoenitati Dicata, the Naumachia Domitiani, and the Porticus Vipsania on the Tiber side of the Equiria. Being dedicated to Castor, and thus dedicated to one of the Roman navy's guiding lights, this temple fits completely within the military program Piranesi plans for the Ichnographia's Equiria. The Templum Castorum does not stand alone with its naval theme, however. Close to the Templum Castorum are the Naumachia Domitiani and the Templum Deorum Larium Parmarini, and, assembled together, these three buildings form a concentrated affirmation of ancient Rome's amphibious forces.