The Château du Landsberg in Heiligenstein includes a Zwinger with two sets of defensive walls. The central part of the castle was built in the late 12th century, and the newer outer castle added onto at the start of the 13th century by Conrad de Landsberg to provide defence for the abbeys of Mont Sainte-Odile, Niedermunster, Truttenhausen and Andlau. More recent additions were made in the 15th century. Herrad of Landsberg was born here around 1130. The castle is privately owned.
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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.