Bydlin Castle was built in the 14th century and appears in documents after 1389. The builder of the castle was probably Niemierza of Strzała or his father Pełka. At the end of the 15th century the stronghold became the Brzezickis’ property, and then the Szczepanoskis’ and the Boners’. In the second half of the 16th century Jan Firlej transformed the castle into the Arian Protestant Church, and at the end of the 16th cent. his son, Mikołaj Firlej, converted it into the Catholic Church of the Holy Cross. The building was abandoned at the end of the 18th century due to escalating assaults of the brigands and since then it has been falling into ruin.
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.