Borsh Castle (also known as Sopot Castle) dates from Antiquity, and its fortifications follow the trace of an acropolis, with four subsequent phases of reconstruction, ranging from the early Byzantine period to the late Middle Ages.
The site is first mentioned in the early 13th century, when archbishop Demetrios Chomatenos wrote of the 'archonship of Sopotos', part of the region of Vagenetia. In 1258, the Despot of Epirus Michael II Komnenos Doukas gave the castle along with Buthrotum and the island of Corfu as dowry for his daughter Helena to Manfred, King of Sicily. It came back under Epirote control soon thereafter, before being once again ceded by Nikephoros I Komnenos Doukas to Charles I of Anjou in 1279. The area returned again to Epirote hands in the subsequent decades, but in the Epirote rebellion against Palaiologan Byzantine rule in 1338–39, it remained loyal to Emperor Andronikos III Palaiologos.
Following the Ottoman conquest, a cadaster from 1431 lists Sopot with 60 households, and as capital of a nahiye. In 1456, troops of King Alfonso V of Aragon were operating in the area of Sobato against the Ottomans. In 1470 it was under Venetian control, under the jurisdiction of the governor of Corfu; at the end of the Ottoman–Venetian War of 1463–1479, the Ottomans laid claim to it and apparently received it, for in 1488 the local Albanian population rebelled against Ottoman rule.
The walls of the castle, which follow the ancient fortifications, survive. In the interior, the medieval fortress was divided through a wall in two. Triangular towers were added later, probably during the middle Byzantine period. In the interior of the castle stand ruins of various buildings and cisterns.
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.