St. John's Church was built between the 12th and 16th centuries, though there must have been churches preceding it. It was heavily damaged during World War II, but it has been restored. The oldest part of the building is the Romanesque tower. The tower dates from the early 13th century.
The choir, in part likewise from the 13th century, is a mixture of Romanesque and Gothic elements, and features two side chapels. To the left of the choir is the vestry, above which there is a room that must once have served as a chapel.
The 14th-century nave is now quite low, as it is covered by a modern ceiling inspired by that of the vestry.
The chapel to the south of the nave dates from the 15th and 16th centuries. Its two bays have Gothic vaults. The vaults of the northern aisle, which an inscription dates 1513, are flamboyant Gothic.
References:Rosenborg Palace was built in the period 1606-34 as Christian IV’s summerhouse just outside the ramparts of Copenhagen. Christian IV was very fond of the palace and often stayed at the castle when he resided in Copenhagen, and it was here that he died in 1648. After his death, the palace passed to his son King Frederik III, who together with his queen, Sophie Amalie, carried out several types of modernisation.
The last king who used the place as a residence was Frederik IV, and around 1720, Rosenborg was abandoned in favor of Frederiksborg Palace.Through the 1700s, considerable art treasures were collected at Rosenborg Castle, among other things items from the estates of deceased royalty and from Christiansborg after the fire there in 1794.
Soon the idea of a museum arose, and that was realised in 1833, which is The Royal Danish Collection’s official year of establishment.