The first Vannes Cathedral was erected around 1020 in Romanesque style. The tower is only structure left from it and accommodates the four bells of the church. The present Gothic building was erected on the site of the former cathedral. Its construction extends from the 15th to the 19th centuries, or if the length of the existence of the 13th century Romanesque bell tower is included, a total of seven centuries of construction. In this period the nave and the ornate gateway at the northern end of the north transept – whose twelve niches, according to Breton custom, were supposed to accommodate the Apostles – were built high. The northern tower is the main remnant of the former Romanesque building, while the vaults and the choir were built between 1771 and 1774.
The façade was carved in 1857 in a neo-Gothic style. Outside, in front of the central pillar of the large gate, stands a statue of the Dominican monk St. Vincent Ferrer, from Valencia. His activities in the 15th century greatly influenced Christianity in Vannes. The northern façade opens onto the garden of the cloister (ruins from the 16th century) and the Rue des chanoines ('Street of the Canons') through the beautiful portal at the top of the north transept, built in a Flamboyant late Gothic style (1514), and decorated with twelve niches designed to house statues of the twelve apostles. The cross, visible close to the northern façade, dates back to the 15th century and was brought from the cemetery.
During the Middle Ages, the floor of the cathedral had been covered by tombstones. For hygienic reasons, only the tradition of burying the bishops in their episcopal church has been preserved. However, some tombstones have been returned and can be seen today. The cathedral has only retained tombs dating back to the 17th century. Two bishops' tombs can be found in the crypt under the choir.
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.