San Fermo Maggiore is a medieval Romanesque church. A church at this site may has been traced to the 8th century, and by the 11th century a second story and belltower was added by the Benedictine order. The campanile was not completed until the 13th century, it contains six bells in F cast in 1755 and rung with the Veronese bellringing art. The exterior has a roofline with pinnacles, and the church once held the tomb of a member of the Scaligers. The interior has later decoration, including an altarpiece of St Francis of Assisi by Giovanni Battista Belloti. The presbytery hosts relics of the saints Fermo and Rustico.
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.