Rainbow Road

Rainbow Road is the name of the last racecourse of the Special Cup in each of the Mario Kart games. These tracks are suspended in the starry night sky or outer space. Most contain few or no rails, putting racers at risk of falling, and each Rainbow Road also contains its unique hazards. Due to these obstacles, Rainbow Road is usually the hardest track in each Mario Kart game.

Super Mario Kart
This Rainbow Road lacks rails entirely and contains 90-degree turns. Rainbow-colored tiles cover the track's surface, and the yellow tiles conceal Coins and jumping humps. This course features flashing Thwomps which can, unlike normal Thwomps, wipe out a racer by touch as well as by crushing unless the racer activates a Star.

Super Mario Kart composer Soyo Oka considers this level's theme one of her favorite compositions.

Mario Kart 64
Rainbow Road is the longest race course in Mario Kart 64 at 2,000 meters and requiring around two minutes per lap. The track differs from the other Rainbow Roads in that it has rails throughout the track. The track features a transparent multi-colored path and with Star-shaped rails running throughout the course. Neon-light pictures of the eight playable characters, plus a portrait of a Boo and a Mushroom in the distance, float in the void. Moreover, a big three-dimensional smiling Star lies in a section of the track. Roving Chain Chomps slide through the course in reverse, tossing into the air any driver who touches them.

The twisting course starts with a huge drop followed by a gentle uphill stretch, passing through a rainbow ring halo. After the ring, racers behold the flashing neon portraits while run through a pigtail bridge, following then towards another shallower drop. Racers turn around a corkscrew to reach a hairpin bend, and then a twisting stretch to go back to the checked line finally.

Although this track may easily be the easiest Rainbow Road track (thanks to the railings), racers can perform an infamous shortcut by making a timed hop to the left (or right, during Extra) during the drop at the beginning.

Mario Kart: Super Circuit
In Mario Kart: Super Circuit, Rainbow Road has rails at the start line. Edges of the course are lined with bounce-jumps. Astute racers can use Mushrooms to perform significant shortcuts. The track has falling stars that can make racers spin out and Thunder Clouds that will shrink anyone careless enough to drive under them. The Bowser's Castle from Paper Mario can be seen in the background. This track is equal with the course of Rage Racer Overpass City. This game also features the Rainbow Road course from Super Mario Kart without the flashing Thwomps.

Mario Kart: Double Dash!!
Dash Panels give a boost of speed to the racers in the Mario Kart: Double Dash!! version of Rainbow Road. This version of Rainbow Road also has rails in parts of the course. It features a helix and a pipe that shoots players to the highest point of the track after reaching the very bottom. It also contains floating sculptures of items, and rains stars that racers can pick up. It has the most pearl-like colors of all the Rainbow Roads. Depending on what difficulty the player chooses, Rainbow Road will take place either over a city or in deep space. The city located below the course could be Mushroom City, according to the design of some of the buildings. When in split screen mode, the city and the item sculptures are removed. The theme music played in the course is a remix of the Rainbow Road from Mario Kart 64, and reappears in Super Smash Bros Brawl as an alternative music theme for the Mario Circuit battle stage.

Mario Kart DS
The Rainbow Road of Mario Kart DS has several rails on certain curves and includes a loop and a corkscrew. Those elements may have been added to ensure challenge; players can place items so their opponents could fall off the corkscrew or the loop. Some multi-colored Pipes and Stars appears in the surroundings of the stage. Additionally, the coloring pattern of this looks different from the other previous Rainbow Roads: here, the stripes on the track follow along it, instead of crossing the track. However, there are glitches on the corkscrew and the loop. If a player drifts and hit the rail it could send the player float up putting he or she whether off the track or on the track back.

Mario Kart Wii
The Rainbow Road of Mario Kart Wii is a new version of the rainbow-colored track. The track is located over the eastern parts of North America, as well as parts of Europe, Africa, and South America. If the player happens to fall off in this track, he/she will burn up in the atmosphere, no matter if there is a section of the course below him/her before getting picked up by Lakitu. This course has a Super Mario Galaxy theme to it, and it even includes floating Star and a part of a Super Mario Galaxy musical piece, Good Egg Galaxy's backround music. A large galaxy can be seen on the background, plus sunlight on the Earth's surface. This course also happens to be Rosalina's expert staff ghost course.

Course Layout
The course begins on a 90 degree slope, located after the starting line. Light drivers are easy to push off in this area, since there are no walls that can help the player from falling off. 3 boost panels are present in this slope. One stretches across the road while the other two are spread apart from each other, such as one being on the right while the other boost panel is on the left, depending on the mode. After the slope is a ramp with a boost panel in it and a sharp turn left. Any vehicle that performs a trick has a risk of falling off on the right end; the worse the drift/handling rating, the more likely the player will fall off.

After the first curve is three more boost panels that stretch across the road and a half-pipe ramp on the very right, plus a turn left. The half-pipe contains floating item boxes for the player to use. After the left turn is a slightly wavy road, in which the player may perform tricks on. Each lap, the road gets wavier, allowing for more tricks to be performed. After the wavy part is a ramp with a boost panel on it, for the player to speed up and perform a trick. The player will then see a very straight road, with two giant holes in the center for the player to fall through. Half-pipe ramps are located to the left and right of these holes, and the player may perform a stunt on the edges of these holes, since the edges of these holes contains small ramps. Both holes contain half-pipe ramps, but the latter one later on doesn't have any item boxes on top of them. After this area is a turn left, then a curve right that has item boxes lying across the road. After the item boxes is the Launch Star which will lead the player, in very high speeds, to the other part of the course. When the player gets out of the Launch Star, there is a very minor twist in the road and a half-pipe ramp that leads the player into another section of the track, making a broad turn right for the player. After this particular ramp is two roads, which split and merge later on in the track. Both will make the player end up in the same area, but one is more elevated than the other and has boost pads in different locations. Both will lead to a ramp with two boost panels on it, with floating item boxes. Past the ramp is where the road merges again. This part has more boost panels with a sharp curve to the left and to the right. The boost panels may give the player an edge or throw the player off course and off the track. Past this area is the finish line, which starts the track over.

Competitions
The November 2009 Competition 2 takes place in Rainbow Road. The player had to race 3 laps, while avoiding the Chain Chomps and Incoming Chomps. The player started the race with a set of Triple Mushrooms. The official description stated, "Anticipating their movements and avoiding them is the key to a good score."

Mario Hoops 3 on 3
Rainbow Road is the unlockable third dribble race from the "challenges" section in the basketball game Mario Hoops 3 on 3. However, this Rainbow Road floats above the clouds and around a clock tower, and not much of the course is fully seen when playing. Podoboos and Bombs come out of holes similar to Bowser Castle.

Trivia

 * F-Zero X and F-Zero GX both have a track named Rainbow Road. They imitate the Mario Kart 64 version of the Rainbow Road, having the same map of the track, and following it basically. They are described as a "Psychedelic Experience". Parts, though not all of it, are rainbow-colored. Unlike the original, they have no barriers in certain areas, and the neon Mario series decor is missing - instead, it just has a plain black background with a watery blue bottom to which careless drivers may fall. In the GX version the background is always changing colors. In addition, when racing the track with the 64DD expansion features, the background song is a heavy metal version of the Rainbow Road song heard in MK64. Of course, there aren't any Chain Chomps.
 * Rainbow Road is the only track in Super Mario Kart which is not numbered.
 * A portion of Good Egg Galaxy's music (from Super Mario Galaxy) is heard on Mario Kart Wii ' s Rainbow Road to match the environment of this course.
 * Interestingly, Mario Kart Wii's Rainbow Road uses square rainbow tiles for the track, just like in Super Mario Kart.