The Monastery of the Cross was built in the eleventh century, during the reign of King Bagrat IV by the Georgian Giorgi-Prokhore of Shavsheti. It is believed that the site was originally consecrated in the fourth century under the instruction of the Roman emperor Constantine the Great, who later gave the site to king Mirian III of Kartli after the conversion of his kingdom to Christianity in 327 AD.
Legend has it that the monastery was erected on the burial spot of Adam's head—though two other locations in Jerusalem also claim this honor—from which grew the tree that gave its wood to the cross on which Christ was crucified.
Due to heavy debt the monastery was sold by the Georgians to the Greeks in 1685. It is currently occupied by monks of the Greek Orthodox Patriarchate of Jerusalem.
The remains of the crusader-period monastery forms a small part of the current complex, most of which has undergone restoration and rebuilding. The crusader section houses a church, including a grotto where a window into the ground below allows viewing of the spot where the tree from which the cross was (reputedly) fashioned grew. Remains from the 4th century are sparse, the most important of which is a fragment of a mosaic. The main complex houses living quarters as well as a museum and gift shop. The monastery library houses many Georgian manuscripts.
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.