The archaeological park is one of the most beautiful places in the city and along the coast of Posillipo. Among the most important sites are the Seiano cave, the underwater park of Gaiola, the imperial villa of Pausilypon, the Odeon, the theatre and the Palace of the Spirits.
The ruins of the Roman villa of Vedius Pollio, also known as the Imperial Villa, include a 2000-seat theatre on the rocky promontary at the end of the Bay of Naples. Some of the villa's rooms can be seen with traces of the wall decorations while its marine structures and fish ponds are now part of the neighbouring submerged Gaiola Park. The villa was built in the first century BC by Publius Vedius Pollio. On his death in 15 BC, the villa was bequeathed to Augustus, and remained in imperial possession for his successors at least until Hadrian, as witnessed by a stamped water pipe. In various points the presence of water supply pipes (coated with hydraulic mortar) show the opulence of the facilities. Augustus demolished at least part of the house and constructed in its place a colonnade in honour of his wife Livia, which he dedicated in 7 BC.
The Palace of the Spirits is an archaeological complex on the coast near Marechiaro and was the nympheum of the villa and also built in the first century BC. The submerged parts of the ruins of the imperial villa and the rich and diverse marine and coastal natural environment can be seen via boat excursions.
References:Visby Cathedral (also known as St. Mary’s Church) is the only survived medieval church in Visby. It was originally built for German merchants and inaugurated in 1225. Around the year 1350 the church was enlarged and converted into a basilica. The two-storey magazine was also added then above the nave as a warehouse for merchants.
Following the Reformation, the church was transformed into a parish church for the town of Visby. All other churches were abandoned. Shortly after the Reformation, in 1572, Gotland was made into its own Diocese, and the church designated its cathedral.
There is not much left of the original interior. The font is made of local red marble in the 13th century. The pulpit was made in Lübeck in 1684. There are 400 graves under the church floor.