Arco Castle ruins are located on a prominent spur high above Arco and the Sarca Valley. The exact date of its foundation is unknown but it existed at least after the year 1000 AD. The area around Arco was inhabited already before the Middle Ages, the castle was said to have been built by the citizens and only later becoming the property of the local nobles.
The counts of Arco, probably of Italian origin, were first mentioned in 1124 deed; they temporarily served as liensmen of the Trent prince-bishops. Though they were raised to comital (Grafen) status by the Hohenstaufen emperor Frederick II in 1221, they had to acknowledge the overlordship of the Meinhardiner princely counts of Tyrol in 1272.
The Counts of Arco were expelled by the Prince-Bishops of Trent in 1349, whereafter the castle fell to the Veronese noble house of Scaliger. Nevertheless, they regained the castle in a local uprising, and in 1413 further strengthened their position by obtaining the status of Imperial immediacy from the hands of Emperor Sigismund in 1413. However, in the long run, they could not prevail against the mighty House of Habsburg, rulers of Tyrol since 1363. Arco Castle was captured in 1579, and the counts had to submit to the Habsburgs in 1614. Their estates were officially seized by Emperor Leopold I in 1680.
The castle was later abandoned after a siege by French troops under General Duke Louis Joseph of Vendôme in the course of the War of the Spanish Succession in 1703. A careful restoration began 1986 and following others in more recent years restorations have found a number of frescoes depicting knights and court ladies of medieval times.
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.