Bisceglie Castle was originally a tower built around 1060-1070 by Normans and enlarged in the 13th century by Swabian counts. The tower was made later higher by the Angevines. Originally the castle was a four-sided building with five towers; today there are three towers left. The North-East tower is adjacent to the 12th century St Giovanni in Castro Church, which was included in the castle as its chapel during the Angevin time. Today the castle hosts an ethnographic museum.
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.