Formerly inhabited by the royal family of Wapol and their servants, the castle is now owned by Dr.Kureha. Since Wapol left, the main entrance has been left open (because snow birds made a nest on top of the door), causing many rooms to freeze over. The armory contains many strong weapons, and in one of the towers is a powerful cannon, which no longer works properly, since birds also made a nest there, as well. It is also where Tony Tony Chopper lived, after the death of Hiluluk, until he left to become the doctor of the Straw Hat Pirates. On the tallest tower there is a flag with Hiluluk's Jolly Roger on it. Ever since then, Kureha uses Drum Castle to establish a medical academy, increasing the Isshi-20 to Isshi-100 in two years.