Piscina Mirabilis

The Piscina Mirabilis (Latin for "wondrous pool") is an Ancient Roman cistern on the Bacoli hill at the western end of the Gulf of Naples, southern Italy.

[6] As it lies 1 km away from the residential and military quarters at Misenum which lay beside each other and which were fed directly by the Aqua Augusta, it is also possible that the cistern belonged instead to one of the many luxurious villas built in this area, like the smaller Grotta della Dragonara and Cento Camerelle cisterns nearby.

In one of them is an opus signinum floor with labyrinth-shaped mosaic tesserae and a central white inlaid panel with limestone polychrome tiles, which seems to date to a more ancient phase.

In the middle of the short central nave there is a 1.1 m deep basin (BB), hollowed out in the floor and provided with an outlet at one end,[7] which served as a so-called piscina limaria (waste-bath, i.e. a settling and drainage basin[7]) for the decantation, cleaning and periodic emptying of the cistern.

A usual, the walls are waterproofed with opus insigninum (cocciopesto in Italian), smoothing the corners through kerbs placed at their bases.