This week during “sportlov” (winter break), Sweden's Royal Palace in Stockholm is hosting a fun and free activity for children and their families. Through March 6, children can do some sleuthing to find out what kind of mischief Little Prince Gustav III (born 1746) has gotten into now. He has hidden the signature stamp belonging to his father, King Adolf Fredrik, and it needs to be found, so guests can decipher and follow clues to solve the mystery in the grand rooms of the palace. Rewards are promised for all children who find the stamp. Instructions are available in Swedish and English in the Bernadotte Apartments.

Saturday and Sunday at 10:30 a.m.
The whole family can also enjoy the exhibit in the Museum Tre Kronor about the castle's medieval history and its transformation as a defense stronghold. No advance booking is needed.