Rosenborg Castle, a splendid Renaissance castle located in Copenhagen, Denmark, is a must-visit for history enthusiasts, showcasing royal interiors, the Danish Crown Jewels, and royal regalia in its Treasury. The castle is generally accessible, though some older sections may have stairs; the surrounding King's Garden is easily navigable. Visitors can opt for self-guided exploration with audioguides for flexibility, or join a guided tour for deeper insights. While open year-round, operating hours vary seasonally, with extended hours in summer, and it's advisable to check the official website for current timings, especially for the Treasury. An adult ticket typically costs around DKK 120-150, and a comprehensive visit to the castle and Treasury usually takes 1.5 to 2.5 hours, plus additional time if exploring the extensive gardens. Booking tickets online in advance is recommended to bypass queues, particularly during peak tourist seasons.