The church can be visited
Havelberger Cathedral

Havelberg Cathedral “St. Marien” is a Protestant cathedral in the Hanseatic city of Havelberg, Saxony-Anhalt. As the former main church of the Diocese of Havelberg, the building is distinguished by its massive westwork, considered an example of the Saxon westriegel.
History+
The origins of the Diocese of Havelberg date back to 948 when King Otto I founded it for missionary work among the West Slavic population. It was one of the earliest dioceses east of the Elbe. The consecration of the cathedral took place on August 16, 1170. After a fire between 1279 and 1330, the main choir was redesigned in the Gothic style. In 1907, a Neo-Romanesque bell story with a ridge turret was added to the westwork.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: Rainer Gindele
This description draws on the facts documented in the linked Wikipedia article; Wikipedia content is licensed under CC BY-SA 4.0. Wording and editing: Mobile History.
Location: 52.8268, 12.0787