Holstenshuus estate was first time mentioned in 1314. It is known as Holstenshuus since 1723, whe the estate was acquired by Christian Adolph Holsten. The oldest wing of the current castle was built in 1579 by Knud Venstermand. Two other wings date from 1643. The major restoration was made in 1863-1868 and again in 1910 after a great fire. The surrounding Rococo park (established in 1753) is open to the public.
References: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.