Piscina Mirabilis was a freshwater cistern situated on the Bacoli cliff at the western end of the Gulf of Naples, in southern Italy. It was one of the largest freshwater cisterns constructed by the ancient Romans and served to provide drinking water to the Roman western imperial fleet at Portus Julius. Additionally, Piscina Mirabilis was a Roman reservoir built by Emperor Augustus in the 1st century AD. After two millennia, Piscina Mirabilis stands as a magnificent architectural marvel of the ancient world. Thanks to Emperor Augustus, these grand structures continue to be admired today, forever serving as a source of pride for Italy. When discussing Emperor Augustus and Piscina Mirabilis, one cannot overlook the significance of Julius Caesar, a Roman general and statesman who played a pivotal role in the transformation from the Roman Republic to the Roman Empire. Therefore, Julius Caesar becomes an important element in this new museum.