St. Peter's Church (Petruskerk) was originally a wooden church, which was burnt down in 1202. The stone church was built in the 13th century. It has been enlarged and several times like in 1492-1509. After the Reformation in 1572 all sculptures and altars were removed from church. During the French Invasion 1672 the church was badly damaged by fire.
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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.