The church can be visited
Sankt-Sebastian-Church

St. Sebastian's Church in Magdeburg is a Roman Catholic cathedral dedicated to Saint Sebastian. Located in Magdeburg's Old Town, it is a part of the Romanesque Road.
History+
The foundation stone was laid around 1015 by Archbishop Gero, who was buried here after his death in 1022. Originally founded as a collegiate church, it was dedicated to Saint Sebastian, John the Evangelist, and Saint Fabian, though the latter's importance diminished after acquiring a relic of Saint Sebastian's head. The Romanesque building burned down in 1188 and 1207. In the 14th century, a Gothic reconstruction took place, replacing the old choir with a larger one. In the early 15th century, the nave was transformed into a late Gothic hall church and reconsecrated in 1489. During the siege of Magdeburg in 1550, cannons were placed on its towers. In the course of the Reformation, the church became Protestant in 1558 and was converted into a Protestant collegiate church in 1573. During the Thirty Years' War, the church burned down in 1631 and was not used for services again until 1692.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://commons.wikimedia.org/wiki/File:Sankt_Sebastian_Magdeburg.jpg?uselang=de
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: 52.1264, 11.6315