Piscina Mirabilis

The Piscina Mirabilis is a monumental Roman cistern built under Emperor Augustus on the Bacoli hill at the western end of the Gulf of Naples, Italy. Known as the "Water Cathedral," it measures 70 metres long, 25.5 metres wide, and 15 metres high, with a capacity of 12,600 cubic metres of water. Its interior features 48 cruciform pillars arranged in four rows of twelve, dividing the space into five naves supporting barrel-vaulted ceilings. Built to supply fresh water to the Roman naval fleet (Classis Misenensis) at the nearby port of Misenum via the Aqua Augusta aqueduct. It became a notable stop on the 18th-century Grand Tour, visited by Mozart, Dumas, and Goethe.