The Plaza is SO big, that it contains FOUR of these large stand-alone castle turrets. Two of these turrets contain production booths with spotlights, projectors, etc. for the stage shows. The other two contain equipment for pyrotechnic and fire effects.
The banners and decorations on the castle are in honor of the park's 25th birthday which is being celebrated all year long.
Happy 25th Birthday, Tokyo Disneyland!!!