Classic course

A Retro Course is a past Mario Kart game's Nitro Course, not counting the Extra Courses from Mario Kart: Super Circuit. They appear in Mario Kart DS, Mario Kart Wii, Mario Kart 7, Mario Kart 8, and Mario Kart 8 Deluxe. They come in the Shell Cup, Banana Cup, Leaf Cup, and Lightning Cup. A Mario Kart course has rarely returned as a Retro Course more than once. Until Mario Kart 8, Retro Courses were identical to their original counterparts, receiving only graphical updates. For example, in Mario Kart 7, courses appear almost identical to the originals, the only differences being the added underwater and gliding sections, while in Mario Kart DS, some Retro Courses appear to be scaled down in graphics due to system limitations of the Nintendo DS. Starting from Mario Kart 8, most Retro Courses are completely redesigned for HD graphics. They usually include new mechanics, new details for the race tracks, and completely new backgrounds, and also support the anti-gravity, underwater, and gliding mechanics. Also new to Mario Kart 8, most Retro Courses have new remixed and/or remastered music. In Mario Kart: Super Circuit, all songs were in 8-Bit. In the Retro Courses (i.e. Mario Kart Wii's GBA Bowser Castle 3), the music was remastered to remove the 8-Bit sound, although some courses, like GBA Shy Guy Beach, retain slight traces of 8-Bit. In Mario Kart DS, all the Retro Courses have their music redone to support the small speakers of the console, with the SNES and GBA courses having the biggest changes to music.

Bell Cup
[[File MK8 DLC-Course - Oddysey circuit

List of Retro Courses
Courses highlighted in red have yet to appear as Retro Courses in a later Mario Kart installment. A hyphen (-) indicates that the course appears as a Nitro Course in its respective game and therefore can not appear as a Retro Course in it or in a previous installment.