A typical visit takes 2-4 hours to explore the main permanent collections and at least one temporary exhibition.
The duration of a visit to Grand Assen Castle, or the Drents Museum, largely depends on individual interest and the number of exhibitions you wish to see. For a general overview of the permanent collections, including archaeology, art, and natural history, allocate approximately 2 to 3 hours.
If you plan to delve deeper into specific exhibits, or if there is a particular temporary exhibition that captures your attention, extend your visit to 3 to 4 hours. Families with children might spend slightly longer, especially when interacting with dedicated children's activities or workshops if available. The museum also has a café, so factor in time for refreshments if desired.