The Little Hagia Sophia mosque is a former Greek Orthodox church dedicated to Saints Sergius and Bacchus in Constantinople (modern Istanbul). It is nonetheless one of the most important early Byzantine buildings in Istanbul. The construction of this church, between 527 and 536 AD, was one of the first acts of the reign of Justinian I.
After the Ottoman conquest of Constantinople in 1453, the church remained untouched until the reign of Bayezid II. Then between 1506 and 1513 it was transformed into a mosque. At that time the portico and madrasah were added to the church.
In 1740 the Grand Vizier Hacı Ahmet Paşa restored the mosque and built the Şadırvan (fountain). Damage caused by the earthquakes of 1648 and 1763 was repaired in 1831 under the reign of Sultan Mahmud II. In 1762 the minaret was first built. It was demolished in 1940 and built again in 1956.
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.