Nardò Cathedral has been since 1986 the episcopal seat of the diocese of Nardò-Gallipoli. The present cathedral probably stands on the site of a Byzantine church. In 1080, a church was built here by the conquering Normans, which was elevated to the status of a cathedral in the early 15th century.
The building has undergone a number of refurbishments. The present façade dates to 1710–1725. The interior contains both medieval frescoes and 19th-century frescoes by Cesare Maccari.
Visby Cathedral (also known as St. Mary’s Church) is the only survived medieval church in Visby. It was originally built for German merchants and inaugurated in 1225. Around the year 1350 the church was enlarged and converted into a basilica. The two-storey magazine was also added then above the nave as a warehouse for merchants.
Following the Reformation, the church was transformed into a parish church for the town of Visby. All other churches were abandoned. Shortly after the Reformation, in 1572, Gotland was made into its own Diocese, and the church designated its cathedral.
There is not much left of the original interior. The font is made of local red marble in the 13th century. The pulpit was made in Lübeck in 1684. There are 400 graves under the church floor.