Château de Tancarville was built in the 11th century by Raoul, the chamberlain of Dukes of Normandy. In the 12th century the square tower was built with 1.65m thick walls. In 1418 at the time of the conquest of Normandy by Henry V of England, the title of Earl of Tancarville was given to John Grey. After the Hundred Years War the Harcourt family restored the castle. The ballroom was built in 1468. In 1709 the castle was partially rebuilt by the Count of Evreux. After 1789, the castle was plundered and partly burned. In the 1960s , the castle served as a summer camp for children.
References:I am a direct descendant of Raoul
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.