Hasselburg estate is located on a site of fortified manor house from the late Middle Ages. The mansion was originally a typical for Holstein, surrounded by moats and in the 18th century reconstructed into a Baroque residence. The mansion is a two-storey building and with illusionistic ceiling paintings. The large gatehouse of 1763 was based on a design of Georg Hofer Gregg. It is one of the largest gatehouses in Schleswig-Holstein.
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.