Archaeologists discover vast ancient pool complex but are baffled over its original function.

Italian archaeologists have announced the discovery of an ancient stone pool, dating to the fourth century BC, in an area of land between Rome and Ostia Antica, to the south-west of the capital.

The discovery of the enormous sunken pool, 48 metres long and 12 metres wide, was made during a one-year dig which began in June 2019, Rome's special superintendency announced today.

"Being faced with such a discovery has left even our archaeologists surprised," stated the special superintendent Daniela Porro, who added that the find proves "how much Rome, even outside its city borders, still has so much to give."

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The oldest remains that have been unearthed on the site date back to the beginning of the fifth century BC.

"The excavation, in all its grandeur, reveals an important place" - explains superintendency archaeologist Barbara Rossi - "which lasted for over eight centuries, as demonstrated by the quantity and above all the quality of rediscovered structures, such as the monumental basin from the fourth century BC, found in all its expanse."

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"An in-depth study of the large number of materials that this investigation has returned to us and continues to return to us - wood, terracotta, metal objects, inscriptions - will reveal the secrets of this extraordinary corner of the greater Rome area."

The find occurred during a so-called rescue or preventative excavation between Via Ostiense and Via di Malafede - an area inhabited since prehistoric times - in a two-hectare site destined for a real-estate development, according to local media.

Photos by Fabio Caricchia - Soprintendenza speciale di Roma Archeologia Belle Arti e Paesaggio.