New course

A Nitro Course is the term used to refer to an original course in the Mario Kart series that is new to the series and has never appeared before. They have appeared in every Mario Kart title, with Mario Kart DS being the first to use the term. In Mario Kart: Super Circuit, the original tracks are called Super Circuit Tracks to distinguish them from the tracks originating from Super Mario Kart, called Extra Tracks. Some of them will or have reappeared in later Mario Kart games as Retro Courses. At least one Mario Circuit, Bowser's Castle, Rainbow Road, a beach- or water-themed course, and a snow-themed course have appeared in each Mario Kart game as a Nitro Course.

Lightning Cup
NOTE: From Mario Kart DS onwards, it is the last cup of the Retro Courses.

Trivia

 * The four worlds after World Bowser in Super Mario 3D World resemble the Nitro Cups (World Mushroom for Mushroom Cup, World Flower for Flower Cup, World Star for Star Cup, and World Crown for Special Cup).