Château d'Hyères was one of the largest castles in Provence. The first mention of the castle dates from 1062. In 1524 and in 1536 the royal armies swept over Provence and Hyères castle was also besieged and conquered. It was reorganised by Charles I of Anjou in 1527 and ultimately dismantled by Louis XIII in a gesture of authority following the destructive religious wars. The castle has been labelled Historical Monument for its important architectural remnants. It offers a spectacular view onto the coast and the islands.
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.