St. Nicholas Church in Altefähr was built of brick in the second half of the 15th century to the site of earlier 13th century chapel. It was painted in 1692 and the tower restored. The next renovation took place in 1737. After the upper third of the tower had collapsed in 1803, the tower was rebuilt. Another extensive renovation of the church took place in 1912-1913. The interior contains valuable wall murals from the 15th century.
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.