Waldeck Castle was first mentioned in 1124. It was owned by the Landgraves of Leuchtenberg, who sold the castle in 1283 to Duke Ludwig of Bavaria. In the Spanish War of Succession, the castle was besieged by imperial troops , taken in October 1704 and demolished by order of Emperor Joseph I. Although the castle was rebuilt, it was burned down in 1794 and since then has been ruined. Since 1982, the ruins have been excavated and restored.
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.