The first written mention of Úsov is from 1260. The castle was built around 1250. Before 1487 the lords of Vlašim modified the castle. In the 16th century, Úsov was in the possession of the lords of Boskovice, an in 1597 it was acquired by the House of Liechtenstein. The Liechtensteins owned the castle until 1945.
The castle was damaged during the Swedish occupation in 1643. During the rule by Hans-Adam I of Liechtenstein, in 1692–1699, it was reconstructed and partially rebuilt into a large three-storey Baroque residence, designed by Domenico Martinelli.
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.