Banana Cup

The Banana Cup comprises four courses, each of which is taken from the nitro cups of previous Mario Kart games, mostly the Mushroom Cup and Flower Cup, although occasionally Star Cup and Special Cup tracks are featured. The cup's symbol is a Banana Peel, and the cup's tracks are slightly more difficult and/or longer when compared to those of the Shell Cup. Its length and difficulty is on par with the Flower Cup. The Banana Cup also returns in Mario Tennis Open for the Nintendo 3DS. It appears after the Flower Cup and before the Champions Cup.

Mario Tennis Open
In Mario Tennis Open, the Banana Cup is the third cup in the World Open series. It is played on the DK Jungle court, and matches have one set for the starting round, three sets for the semifinals, and five sets for the finals. This cup can be unlocked by beating the Flower Cup, and once beaten will unlock the Champions Cup. The CPU difficulty is one step harder than that of the Flower Cup's.

Completion rewards in the Mario Kart series
Winning the Banana Cup in the Mario Kart series can award the player with various bonuses, depending on the game. Additional cups unlocked are excluded from this list.

Mario Kart DS

 * All retro cups (includes Banana Cup) on 50cc: Daisy
 * All retro cups (includes Banana Cup) on 100cc: Waluigi
 * All retro cups (includes Banana Cup) or all nitro cups (excludes Banana Cup) on 150cc: Seven karts for each playable character
 * All cups on 150cc: 150cc Mirror class
 * All retro cups (includes Banana Cup) or all nitro cups (excludes Banana Cup) on 150cc Mirror: R.O.B.
 * All cups on 150cc Mirror: All karts for each playable character

Mario Kart Wii

 * Shell and Banana Cups: Leaf Cup
 * 1 star rank or higher on all retro cups (includes Banana Cup) on 50cc: Cheep Charger
 * 1 star rank or higher on all retro cups (includes Banana Cup) on 100cc: Bowser Jr.
 * 1 star rank or higher on all retro cups (includes Banana Cup) on 150cc: Jetsetter
 * All cups on 150cc: 150cc Mirror class
 * 1 star rank or higher on all cups on 150cc Mirror: Rosalina

Mario Kart 7

 * All cups on a single cc class: Mii
 * 150cc Banana Cup: Honey Queen
 * All cups on 50cc, 100cc, and 150cc: 150cc Mirror class

Mario Kart 8
Most unlockable characters in Mario Kart 8 are unlocked at random upon winning Grand Prix cups (separate cups must be played to unlock characters), which includes the Banana Cup. Characters that can be unlocked include Rosalina, Metal Mario, Lakitu, Toadette, Baby Rosalina, Pink Gold Peach, Iggy Koopa, Roy Koopa, Lemmy Koopa, Larry Koopa, Wendy O. Koopa, Ludwig von Koopa, Morton Koopa Jr., and Mii. Mii is unlocked upon the eighth Grand Prix cup victory, unless an amiibo is used to unlock Mii beforehand.

In addition, the Gold Standard body can be unlocked by getting a 1 star rank or higher on all non-DLC cups (including the Shell Cup) on any one engine class, and the 150cc Mirror class can be unlocked by winning all 150cc cups.

Mario Kart 8 Deluxe

 * 1 star rank or higher on all cups on 150cc Mirror: Gold Standard
 * All cups on 200cc: Gold Mario

Trading Card info
"The Retro Cup racing festival peels off four challenging drives with the Banana Cup. It consists of one track from N64, one from Game Boy Advance, one from DS and one from GameCube...all with somewhat challenging levels of difficulty for Grand Prix or Time Trials competition."

Trivia

 * In Mario Kart 8, this is the only cup in the game with all courses taking place in the daytime, and is the only Banana Cup so far to have this trait. It is also one of two cups in the game to use the same character as Staff Ghosts in two tracks of the same cup (being Peach in Dry Dry Desert and Royal Raceway), the other being the Egg Cup (being Mario in Excitebike Arena and Mute City).

Trofeo Banana Bananen-Cup