Where would a new Hogwarts student shop for their school uniform? Madam Malkin's Robes in Diagon Alley! This Christmas tree ornament features the gray brick building with a purple painted entrance where witches and wizards also purchased dress robes, traveling cloaks and more. For a more enchanting display, insert the bulb of a standard miniature light string through the rubber grommet on the ornament to create a special lighting effect.