The Château de Lacassagne is thought to date from the latter half of the 15th century, with additions and alterations made in every century until the 19th century. It originated as an ancient salle (hall) and was altered in the 15th century with the addition of a spiral staircase and windows. A residence was added in the 17th century. On the first floor, in a room known as the Salle des Chevaliers de Malte, the painted decor was done between 1620 and 1640 for Jean Bertrand de Luppé, prior of St Gilles, and intended as a replica of the grand council hall of the Knights of St John of Malta. Among the pictures are copies of Matteo da Leccio's paintings representing the attack on Valletta by the Turks in 1565. The originals were in the council chamber of the Grandmaster's Palace in Valletta, Malta and were destroyed by Napoleon Bonaparte in 1798.
In the 19th century, a west wing was added to the main building. The castle is not 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.