The Yellow Fortress or Yellow Bastion is a cannon fortress at the entrance of the 'Walled City of Vratnik'. It was built between 1727 and 1739 in area called Jekovac, close to the Jajce Barracks and the Jekovac water reservoir. It served as one of the defense points against the Austro-Hungarian troops in 1878. The fortress was damaged and rebuilt several times. The most recent renovation took place in 1998.
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.