Grolman Bastion was part of the Königsberg fortification system. Named after General Karl Wilhelm von Grolman, it was finished in 1851. It was strengthened with casemates and caponniers inside its wall and consists of lesser Oberteich and Kupferteich Bastions. The Bastion was considerably damaged by Soviet Army in the World War II. There was a vegetable storehouse in the Bastion during the Soviet time. Nowadays this fortress memorial is under reconstruction.
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.