Short answers, pulled from the story.
King Christian IV of Denmark commissioned Rosenborg Castle in 1606 as a new summer residence. The project marked the beginning of a decades-long architectural experiment that defined his reign.
Architects Bertel Lange and Hans van Steenwinckel the Younger oversaw the structural planning during the construction period. Their work transformed the initial modest country house into a symbol of royal power and artistic ambition.
Danish regents used Rosenborg Castle as their primary royal residence until approximately 1710. After this date, the building saw very limited use as a home for royalty and functioned as an emergency shelter only twice during its history.
Rosenborg opened its doors to the public in 1838 when it became state property. The museum houses artifacts spanning from the late sixteenth century under Christian IV through the nineteenth century.
An estimated 2.5 million visitors walk through the gardens every year seeking a retreat from city life. This area holds the distinction of being the country's oldest royal garden in Denmark.