Pfarrkirche St. Martin Nienburg

The heart of Nienburg's old town is the parish church of St. Martin. The church received its present appearance - apart from the tower - in the 14th and 15th centuries. Remains of the original Romanesque church from the late 12th century can be found in an exposed plinth passage on the south side and in the bricked-up Romanesque gate on the north wall. The reason for the reconstruction is probably the division of the county of Hoya in 1345. While Count Gerhard resided in Hoya, Count Johann made Nienburg his residence and thus the church the burial place of his branch of the family. However, the appearance of St. Martin's Church is largely determined by its tower. The sandstone base dates back to the 13th century. The tower was badly damaged during the Thirty Years' War and replaced by an emergency tower after the war. In 1896, this emergency tower was demolished and replaced by the neo-Gothic tower, which is around 72 meters high.

The vaults of the tower contain the sarcophagi of Counts Jobst II and Otto VIII and their wives. Until 1830, the tombs had stood in the choir, under which the counts' crypt was located. The entrance behind the altar has since been walled up. Other furnishings in the church include a whole series of epitaphs of various Nienburg families and individuals. The version of the cross ribs in the side aisles corresponds to the uncovering of 1993, in the choir to that of 1988. Presumably all the paintings were covered with lime in the 16th century.

The famous Twelve Apostles by the Master of Osnabrück (around 1520), which were lost for a long time, are among the special art treasures of this church. They only returned to St. Martin's Church in 1978. A joint campaign by the church and the town rescued them from an auction in London. The new organ was installed in 1997 by the Jann workshop from Alkoven near Regensburg, based on a design by the architectural firm Grundmann and Hein, Hamburg. It has 38 stops in three manuals and a pedal division and a Zimbelstern.