Extra Tracks are unlockable Tracks exclusive to Mario Kart: Super Circuit. There is a total of five Extra Cups, corresponding with the number of Cups in the Super Circuit Tracks. There it the Extra Mushroom Cup, Extra Flower Cup, Extra Lightning Cup, Extra Star Cup, and Extra Special Cup, with four Tracks in each one. They are actually Retro Tracks from Super Mario Kart, the first Mario Kart game. So all twenty of them are in Mario Kart: Super Circuit. Some obsatcles have been removed from them.
Each Extra Cup becomes assessable once the Super Circuit Cup by the same name is beaten with a least a one star ranking.