The Romanesque Abbey church was constructed in the mid-11th century and contains many beautiful 11th- and 12th-century murals which are still in a remarkable state of preservation. It has been a UNESCO World Heritage Site since 1983.
The cruciform church carries a square tower over its crossing. The transept was built first, then the choir with its ambulatory with five radial chapels in the polygonal apse. In the next building campaign, three bays of the nave were added, the bell tower and its porch, and finally the last six bays of the nave. The bell tower is finished by a fine stone spire more than 80 meters high, added in the 14th century (and restored in the 19th century).
The barrel vaulted nave is supported on magnificently-scaled column with foliate capitals.
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.