The Roman cistern of road Cristoforo Colombo, Rome, Italy: operating mode and connection with the old Appian Way

Abstract

The cistern is located on a hilly area consisting of the middle Pleistocene p. p. pyroclastic formation Pozzolane Rosse in road Cristoforo Colombo about 625 m SW of old Appian Way. It came to light in 1940 as a result of earthworks carried out for the construction of the Imperial Way, connecting downtown with the area in which the Universal Exhibition of Rome (EUR) would have been developed in 1942. This hydraulic structure, built with a cylindrical shape in the late second or early third century ad, was excavated in the Pozzolane Rosse. The inner part is composed of a trapezoidal entrance vestibule, from which starts a shaft used to transport water to the outside, two concentric corridors, one outer with 10 compartments, one inner, and a central compartment, covered with hydraulic mortar and communicating via openings. The cistern was fed by rainfall that converged on the central hole of the impermeable cover in direct communication with the corresponding central compartment of the cistern itself. The actual volume used for the water supply is 573 m3. The order of magnitude of water that could enter the cistern in a year is 26,334 m3. The water was used for a fundus in the southern suburbium of Rome, which most probably included a villa connected to old Appian Way through a secondary road.