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:The Church of St Donatus name refers to Donatus of Zadar, who began construction on this church in the 9th century and ended it on the northeastern part of the Roman forum. It is the largest Pre-Romanesque building in Croatia.
The beginning of the building of the church was placed to the second half of the 8th century, and it is supposed to have been completed in the 9th century. The Zadar bishop and diplomat Donat (8th and 9th centuries) is credited with the building of the church. He led the representations of the Dalmatian cities to Constantinople and Charles the Great, which is why this church bears slight resemblance to Charlemagne's court chapels, especially the one in Aachen, and also to the Basilica of San Vitale in Ravenna. It belongs to the Pre-Romanesque architectural period.
The circular church, formerly domed, is 27 m high and is characterised by simplicity and technical primitivism.