Visit Lecce: discover the baroque style and more

The largest and oldest cistern of the Roman Empire

Visit Piscina Mirabilis Bacoli Miseno Guided tour
Our guided tour at the Piscina Mirabilis

Visit with us the Piscina Mirabilis, the largest underground water basin of Roman Empire in Bacoli, Italy.

Many know the underground water basin of Istanbul (Constantinople) which was built 500 years after the one present in Bacoli, in southern Italy.

Let's go back in time and go to a place where nature, history and myth are intertwined. We are west of Naples in the area of the Phlegrean Fields, from the Greek word phlegràios which means ‘burning’ because it is characterized by an intense volcanic activity that manifests itself with thermal springs, volcanic lakes, sulphate and numerous active volcanoes.

In this territory have been set some of the most important myths of classical antiquity (the Cumana Sibyl, the gate of the Underworld), also in the Phlegrean Fields was founded Cuma, the first Greek colony of the West.

The beauty of the landscape led this area to be chosen as a holiday resort of the Roman nobility especially in the town of Baia, while the Gulf of Pozzuoli with the ports of the ancient Puteoli (Pozzuoli) and Miseno was chosen as the seat of the Roman fleet.

What's the best way to see Piscina Mirabilis - Bacoli - Miseno?

The itineraries in the area of the Archaeological Park of Phlegrean Fields develop around 25 sites including amphitheatres, temples, theatres, museums and archaeological areas. 

A rich historical and archaeological heritage, even underwater, that we begin to tell you and that you can enjoy with our guided tours.

The starting point we have chosen is a monument located in Bacoli, the Roman Bauli, which has aroused wonder in its visitors since the time of the Grand Tour.

It was the scholars of the late seventeenth century who called the building: Piscina Mirabilis, for the monumentality of the structure and the suggestion of the interior, still in good condition.

Roman Empire architecture building in Italy Piscina Mirabilis
Interiors of the Piscina Mirabilis

Guided authorized tours in Piscina Mirabilis
Interiors of the Piscina Mirabilis

A curiosity: inside the Piscina Mirabilis you can find numerous graffiti left by scholars and travelers of the Grand Tour who wrote or engraved their name or the date of their visit on the walls. Among these visitors are Mozart, Goethe and Dumas.

The Piscina Mirabilis is certainly one of the most amazing architectural works of the Roman age.

It is the largest and oldest of the cisterns built by the ancient Romans and was used for the water supply of the cities of Misenum, Bauli and the numerous ships of the Roman imperial military fleet: the Misenensis Classis then became Praetoria Misenensis Pia Vindex, moored in the port of Miseno.

The Piscina Mirabilis is actually the point of arrival, after a path of about 100 km, of the Aqua Augusta Campaniae better known as the Serino Roman Aqueduct, built in the age of Augustus (between 33 and 12 BC).

It was a large reservoir that could hold 12,600 cubic meters of water.

The structure is partly excavated in the rock and partly built in a reticulated work (opus reticulatum).

The walls were made waterproof through a cocciopesto coating (opus signinum).

The opus reticulatum of the Piscina Mirabilis Roman Empire building architecture
The opus reticulatum in the Piscina Mirabilis

The numbers reveal the grandeur of the structure that measures 70 meters in length, 25 meters in width and a height of 15 meters.

The interior space seems to be that of an underground cathedral divided into five long naves and thirteen short by four rows of twelve cruciform pillars that support the barrel vault.

Cruciform pillars of the Piscina Mirabilis roman empire building
Cruciform pillars of the Piscina Mirabilis

At the vault were placed openings that allowed the extraction of water through hydraulic machines placed on the terrace; a system of canals provided for the distribution of water.

A series of windows at the top of the side walls and the upper wells allowed ventilation and lighting of the room.

The reservoir was periodically emptied and cleaned. Access was through two stairs at the corners. 

Functional to the cleaning of the large cistern was a tank dug at the bottom of the central nave and 1.10 meters deep.

access stairs to the Piscina Mirabilis Italy roman empire architecture building design
Access stairs to the Piscina Mirabilis

access stairs to the Piscina Mirabilis Italy roman empire architecture building design
Access stairs to the Piscina Mirabilis

Numerous ancient remains are found in Bacoli.

Not far from the Piscina Mirabilis there is another system of cisterns known as 'Cento Camerelle' or 'Prisons of Nero' pertaining to a large villa, in the past renowned for its wealth, belonged to the orator Quinto Ortensio Ortalo (I sec. BC).

A little further north is the so-called Tomb of Agrippina: it is actually an odeion (a small theatre) of another Roman villa, then transformed into a scenic nymphaeum (a fountain) on the sea.

Legend has it that Agrippina Minore was buried here, had her son Nero kill her.

When is Piscina Mirabilis - Miseno open?

Access to the Piscina Mirabilis is subject to the availability of the caretaker who must be contacted privately to request the opening.

Enjoy the bay with us! 

If you need a break before leaving for a new itinerary in the Archaeological Park of Phlegrean Fields, in Bacoli there is the opportunity to stop at the beautiful beaches to enjoy the stunning sea of the bay.

In our guided tours we can also include moments of relaxation to share together in one of the private beach clubs where access is allowed only by invitation.

beach club in Bacoli Napoli Naples Italy
Walking down the stairs to the private beach club in Bacoli

How we can help you? 

👉🏽 Our guided tours give you the opportunity to live the tourist experience without hassle to save time and optimize your journey.

👉🏽 Please feel free to contact us at, we will be happy to help you in case you desire to take part in our customized guided tours in the bay of Naples or are looking for inspiration to plan your next travel experiences to Italy.

We will continue to talk about these places in the next Roman itineraries. 

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