Tower of the Wing Cap

Tower of the Wing Cap is the Cap Switch stage that unlocks the Wing Cap. It is unlocked when you obtain 10 stars and look into a light in the first floor of the castle.

Inside The Tower
In certain personalized copies of the game, the player can enter one of the 5 towers in this level, usually by flying into a window or a cracked segment of the wall, leading to a small sub-level with a single star requiring the player to platform through the level. Oddly, the player usually ends up at the bottom of the tower and must platform upwards for the star. If they appear at the top, they must traverse downwards. This level usually does not require the Wing Cap, instead using cannons if regular platforming is impossible.