The Palazzo della Ragione is a medieval town hall in Padua. The building, with its great hall on the upper floor, is reputed to have the largest roof unsupported by columns in Europe; the hall is nearly rectangular, its length 81.5m, its breadth 27m, and its height 24 m; the walls are covered with allegorical frescoes; the building stands on arches, and the upper storey is surrounded by an open loggia, not unlike that which surrounds the Basilica Palladiana in Vicenza.
The Palazzo was begun in 1172 and finished in 1219. In 1306, Fra Giovanni, an Augustinian friar, covered the whole with one roof; originally there were three roofs, spanning the three chambers into which the hall was at first divided; the internal partition walls remained till the fire of 1420, when the Venetian architects who undertook the restoration removed them, throwing all three spaces into one and forming the present great hall, the Salone. The new space was refrescoed by Nicolò Miretto and Stefano da Ferrara, working from 1425 to 1440.
A tornado destroyed the roof and damaged the building on 17 August 1756.
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.