The first Christian church was probably a wooden church. Of this church there is no trace, but the baptismal font in the Church today has probably belonged to this church. In the 1220s a new stone church of considerable size was built in round-headed Romanesque style and consisted of a nave with four pillars, chancel with two cross-arms and apse, an extension in the rear of the chancel where the altar was placed. A large tower in the west would be part of the building, but it never came to execution. The nave is left intact to this day. Lau church is the island’s largest country church. It is famous for its unique acoustics.
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.