According to the legends, Al-Mansur (legendary Moorish leader) was defeated near Calatañazor Castle in a bloody battle against Christian troops in 1002. The fortress originally had two quadrangular towers on the corners and a keep. Later on, circular towers were added to the southern wall and semi-circular ones next to the main entrance. The current appearance dates mainly from the 14th century.
The castle is part of the walled village of Calatañazor but separated from it by a dry moat that was cut out of the rock. On the castle's irregular enclosure there are ruins of several towers and the keep, which is situated next to the entrance over the moat.
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.