Klobuk is a medieval fortress in Bosnia and Herzegovina. It is located on the karst plateau of Mirotinske grede, near the village of Klobuk, Trebinje, in the Republic of Srpska entity of Bosnia and Herzegovina. It is believed to have been built in the 9th century. In the work of Constantine Porphyrogenitus De Administrando Imperio in the middle of the 10th century, he mentions a town in the parish of Vrm in the county of Travunija. The fortress is also mentioned during the reign of archon Stefan Vojislav in the 11th century. The town of Klobuk was part of the state of Nemanjić until 1321, when this area passed into the hands of Bosnian rulers. It was first in the possession of the Sankovićs, and then from 1395 to 1442 in the possession of the Pavlovićs, who took it from Sankovićs. Then in 1442, it was taken over from Pavlović by Stjepan Vukčić Kosač sometime before 1442. During the 15th century, it was governed by a knyaz on behalf of the lord, and also had the castellan as a military commander.
The Ottomans captured Klobuk in 1477, and since then an Ottoman army crew has been stationed in the fortress until 1878, when they offered fierce resistance to Austro-Hungarian forces. The fortress gained importance after the Peace of Karlovac in 1699, when it became a prominent point towards the possessions of Venetia in Dalmatia and towards Montenegro. During the Ottomans, it belonged to the Sanjak of Herzegovina.
Inside Klobuk, in front of the former church, on the foundations of which the mosque was built, there is a stećak tombstone of the nobleman Vukosav Zemlić. Today, only towers up to 6 meters high are preserved, and some walls.
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.