The Lotrščak Tower is located in an old part of town called Gradec of Zagreb. The tower, which dates to the 13th century, was built to guard the southern gate of the Gradec town wall. The name is derived from Latin campana latrunculorum, meaning 'thieves' bell', referring to a bell hung in the tower in 1646 to signal the closing of the town gates.
The Grič cannon is one of the Zagreb landmarks. In the 19th century, a fourth floor and windows were added to the tower and a cannon was placed on the top. Since 1 January 1877, the cannon is fired from the tower on Grič to mark midday. The cannon was to give the sign for exact noon for the bell-ringers of the city's churches.
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.