The Teutonic castle risen above the river in Pisz was named in turn Johannisburg. The first privilege regarding a settlement around the castle was granted in the year 1367. Pisz gained its civic rights in 1645 and officially received the name of the castle. The local people of Mazury called the castle 'Jańsbork' (Johannisburg), and this name remained until 1946. Today only fragments remain of this castle.
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.