The church of Notre-Dame d’Alleaume was built on a site where the remains of the Gallo-Roman town of Alauna have been found. The edifice which was altered in the 13th, and 15th centuries (enlargements) and in the 18th century (re-working) retains some elements of the 12th century (porch in the south wall of the choir, door in the south wall of the nave). The lintel of a door in the south wing of the transept shows an older bas-relief (probably from the mid-11th century). It shows two saints under arches (Peter and John), a down bearing an olive branch and the mystic lamb, an image of Christ. It has not been possible to attribute this rather archaic work to any sculptor of the Romanesque period in the Cotentin region.
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.