The Château des Quat'Sos name is of Gascon origin, describing the identical appearance of the four corner towers, the 'Four Sisters'. The castle is located on the promontory overlooking the confluence of the Garonne and the tributary Charros.
In 1224, permission was granted by King Louis VIII of France to build a castle. The castle was completed by King Henry III of England, while Duke of Aquitaine, to defend the English Duchy of Gascony. During the Hundred Years' War, the castle was fiercely disputed between English and French.
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.