The church can be visited
Cathedral of St. Peter

St. Peter's Cathedral in Osnabrück is a late Romanesque cathedral that has shaped the city's skyline for centuries. As the episcopal church of the Diocese of Osnabrück, it combines historical depth with architectural significance.
History+
The origins of the cathedral date back to 785, when the first church was built just 15 years after the diocese was founded by Charlemagne. However, this early structure fell victim to the Normans about 100 years later. The cathedral's current form gradually developed after a fire around 1100. Among the oldest surviving structural elements are the Romanesque crossing tower, the north front, and the Romanesque-Gothic west facade.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: https://de.wikipedia.org/wiki/Datei:Osnabr%C3%BCck_Dom_Westseite.jpg
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: 52.2772, 8.0448