In the Roman times the city of Peqin was known by the name of Clodiana, an Illyrian-inhabited territory. The foundations of the castle are thought to date from the Roman period, the time of the construction of the Via Egnatia. Its walls at one point had a height of around 12 metres. The castle was later rebuilt and expanded during the Turkish occupation of Albania, at which time it was passed into the control of the Sipahi (lord) of the local fief, who added a palace and a harem. The last resident of the castle was Demir Pasha.
The castle was equipped with subterranean tunnels which served as exits several km away from the city in difficult times. Similarly, clay pipes have been found in the walls of the castle, which archaeologists believe is an indication that water was supplied from outside the castle during wartime.
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.