Piscina Mirabilis

Bacoli, Italy

The Piscina Mirabilis was a freshwater cistern on the Bacoli cliff at the western end of the Gulf of Naples. One of the largest freshwater cisterns built by the ancient Romans, it was situated there in order to provide the Roman western imperial fleet at Portus Julius with drinking water.

The cistern was dug entirely out of the tuff cliff face and was 15 metres high, 72 metres long, and 25 metres wide. It was supported by vaulted ceilings and a total of 48 pillars. It was supplied with water from the main Roman aqueduct, the Aqua Augusta, which brought water from sources in Serino near Avellino, 100 kilometres distant, to Naples.

The ancient cistern is currently in private hands, but parts of it may still be visited by the public.



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Founded: 27 BCE - 14 AD
Category: Prehistoric and archaeological sites in Italy

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4.5/5 (based on Google user reviews)

User Reviews

E.ByGum (2 years ago)
Not a great start, we arrived around 3pm on Sunday signs said open until 5pm but it was locked up and deserted. So we went to wander round nearby Baia (amazingly fantastic) and chatted to the very helpful superintendant. He rang Mirabilis and discovered that it would be open shortly so we went back. It was worth it: truly incredible. Guided tour is Italian only so research before you go. Would have been 5 stars if staff hadn't popped out to lunch when we first arrived. There's a website check it is open before you go. But do go, much bigger than the cisterns in Aptera Crete.
Markus Salmela (2 years ago)
Interesting piece of ancient history. A bit hidden but definitely worth visit. English guide available.
Quentin Gisserot (2 years ago)
Can’t miss it if you’re an archeology fan. It’s been reopened by an association as of last year, you need to contact them ahead of time on the website.
Federica Pasini (3 years ago)
A must visit architecture, build in a roman period to provide the entire area with clean water. Huge space and work!
Paige Ladd (3 years ago)
Even on a rainy day, the visit was wonderful. The fact that they nobody put up too many signs, or special lighting, or souvenir shops was so restful. The place is spectacular without a lot of help. I did appreciate the modern stairway they have installed. It’s empty now, but used to be a giant cistern built to resupply the water on ships of the Roman fleet. Very long aqueduct kept it full, except when it was drained to get rid of silt. I paid €7 for the guided tour, and it was 100% worth it. If I get the chance, I’m certainly going back. It’s easy to schedule a tour time by email. The place is open Friday Saturday and Sunday.
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