Underwater archaeologists have discovered the partially submerged city of Baia in the Gulf of Naples, Italy. The project, led by CSR Restauro Beni Culturali and Naumacos Underwater Archaeology and Technology, suggests that the mosaic floor dates back 2,000 years. The floor, laid towards the end of the Roman Empire, covered about 250 square meters and featured intricate geometric patterns made of finely cut pieces of marble.

Bacoli’s mayor, Josi Gerardo Della Ragione, called the marble floor “the magic of Baia Sommersa.” He told Archaeology Magazine: “This discovery allowed visitors to immerse themselves in history and explore the hidden wonders beneath the sea’s surface.”

Traditional mosaics used small, uniform pieces called tesserae, but the opus sectile technique involved fitting larger, carefully shaped pieces together like a puzzle. Knewz.com found that such floors were usually found in prestigious buildings such as villas, palaces and public baths. The researchers also noted: “It was a very costly and demanding undertaking for the owner of the villa, who had to make do with recycled materials to create the desired design.”

Over 2,000 years ago, Baia was something like the Las Vegas of the Roman Empire – a resort town about 30 km from Naples on Italy’s west coast. Thanks to its hot springs, magnificent villas and luxurious lifestyle, it had become a favourite place for poets, generals and other important figures. Even emperors such as Nero and Hadrian had come here to enjoy the luxury.

Over time, however, volcanic activity and the gradual subsidence of the earth’s surface caused large parts of Baia to sink underwater. Due to the volcanic craters in the area, the town became known as the Phlegraean Fields, or “Burning Fields.” The remains became part of an underwater park where divers could explore submerged buildings, mosaics, statues and Roman architecture.

John Smout, a researcher who worked with local archaeologists to study the site, told the BBC: “There are many stories of intrigue associated with Baia.” Rumours said that Cleopatra fled Baia by boat after the assassination of Julius Caesar in 44 BC. It was also said that Julia Agrippina planned the death of her husband Claudius in Baia so that her son Nero could become Emperor of Rome. Smout further explained: “She poisoned Claudius with deadly mushrooms. But when he somehow survived that same night, Agrippina had her doctor give him an enema with poisonous wild pumpkin plant, which eventually helped.”

At that time, archaeologists were carefully recovering any loose fragments associated with Baia. The marble they found was cleaned and studied to learn more about its origins. As the investigation continued, it was likely that even more hidden treasures could be found in Baia. Divers, historians and photographers had already discovered submerged rotundas, colonnades and even the famous Temple of Venus, which was a thermal sauna.

Afterwards, visitors could explore the ancient ruins of Baia in one of the few underwater archaeological parks in the world. The dilapidated buildings and well-preserved statues on the seabed could be viewed from glass-bottom boats, while snorkeling or even scuba diving.