Loučeň Castle was built on the site of a former medieval fortress. The first mention of this fortress dates back to 1223 and was discovered in the testimonial of the Prague bishop Peregrinus. This year is also considered the first official mention of the village of Loučeň. From that time until 1618, several lords and peasants alternated as owners of the fortress.
In 1612, the castle of Loučeň and other adjacent villages were owned by Václav Berka of Dubá the Elder, a very wealthy nobleman who did not sympathize with Emperor Ferdinand II. Therefore, in 1620, after the Battle of White Mountain, Václav Berka left the country and the castle was confiscated in 1622 due to his participation in the anti-Habsburg uprising. A year later, all of Berka's property was purchased by Adam of Valdštejn.
During the Thirty Years' War, all the surrounding villages in the Nymburk region were heavily affected by the invasion of armies. The dilapidated fortress in Loučeň was not renovated until 1704-1713, when Karel Arnošt of Valdštejn began to transform it into a Baroque castle. A chapel was also added to the castle, which was later converted into the Church of the Assumption of the Virgin Mary. After Karel Arnošt's death, his daughter Eleanora took over the estate, and she passed it on to her daughter Maria Anna. She was very determined, persecuted evangelicals, and tightened the requirements of serfdom. Maria Anna married Josef Fürstenberg, and thus the ownership of Loučeň Castle passed from the Valdštejn family to the Fürstenbergs.
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.