Nidzica castle construction was begun around 1370. The Pfleger of the Teutonic Knights made it his residence in 1409. On 12t July 1410, the undefended castle was captured by the Polish forces on their way into the interior of the State of the Teutonic Order. At the time of the Hunger War of 1414 the castle was put under siege by the Polish knights and taken after eight days on the 6th of July. In 1454 the castle was occupied by the Prussian Union and in February 1455 was taken by the Czech army led by Jan Kolda ze Zampachu, who had repulsed an attack an by the forces of the Teutonic Knights on 28 April.
In 1517 the inner ward was built up and reinforced. In 1784 a fire consumed the innter ward. In 1812 the castle was devastated by French forces. The castle was rebuilt from 1828-1830 into a court and a prison. The Soviet army bombarded the castle in 1945 and it remained in ruins until its rebuilding in 1961-1965.
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.