3DS Neo Bowser City

Neo Bowser City (known as Koopa City in the PAL regions) is the third course of the Star Cup in Mario Kart 7. It is a neon-lit city-themed course themed after Bowser, the first track of this sort to not be a version of Bowser's Castle. Neon signs are everywhere and images of Bowser himself and his signature emblem can be seen in various places.

Neo Bowser City is the second course in the Mario Kart series that is placed entirely in the rain, the first being Luigi Circuit from Mario Kart: Super Circuit. This is also the first course related to Bowser that is not a castle. Its theme is a remixed version of Toad Circuit / Mario Circuit and the title theme of Mario Kart 7. It also contains remixed parts of songs from previous installments, such as Mario Kart 64s Toad's Turnpike, and Mario Kart Wiis Luigi's Circuit/Mario Circuit.

Neo Bowser City also appears as a retro track in Mario Kart 8. In this game it is the first track of the Bell Cup, a cup that comes with the Animal Crossing x Mario Kart 8 add-on content pack.

Description
This course takes place in a brightly lit city in the rain. A large percentage of the course is winding roads with moving neon arrow railings. There is a small upward spiral section in the middle of the track that goes up a tower. Traction is decreased due to the rain. There is a tunnel close to the end of the course, that leads to a road that is covered with puddles. At the end, there is a ramp that uses the glider. A billboard is seen near it with a picture of either Bowser (said picture is his artwork from New Super Mario Bros. Wii), the player's view, or an animated "Overtake" ad from Toad Circuit. If gliding players veer left (right in mirror mode) from the starting line, they can fly over a Koopa Clown Car with a fan to give them lift enough for the first bend; in higher engine classes, however, they must steer back quickly to avoid hitting the wall.

Course layout
The course starts with an S-bend; however, players must steer back in quickly to avoid hitting the wall. Just before the player enters the air vent area, it is possible to be pushed through the guardrails by a heavier opponent. After that, the race continues under a tower with air ducts. Then there are two soft turns and a red tunnel. After many turns, the player exits and reaches the winding part of the road, which consists of three turns. Then, there is a shorter tunnel that leads to a road all to the left, that is covered with puddles. At the end, there is a ramp that uses the glider and then the lap finishes.

Shortcuts

 * After the S-bend, players can cut through the mud with a Mushroom. They must steer back in quickly to avoid hitting the wall.
 * Near the finish line, if players use a Mushroom or the Koopa Clown Car air current, they can glide into a secret zone on the S-bend under the red tunnel.

Mario Kart 8
Neo Bowser City returns to Mario Kart 8 as a retro course in the second DLC pack Animal Crossing × Mario Kart 8 and the first track of the Bell Cup. The track has been updated to HD graphics, with the city background given an overhaul in design, featuring a glass tunnel where anti-gravity vehicles are driving in, and with more distinctive architecture, instead of having mushroom hills on the far background. The start and finish banner has been redesigned, featuring hexagon patterns behind the Mario Kart logo, and on the two neon pillars (previously one) supporting the banner.

The new Bowser insignia that is now used in this course is also modeled around a hexagon. The blimp with a screen on it has been removed. Billboards now show an animated picture of the name of the course, along with Bowser in it, instead of displaying an ongoing video of the player's point of view, an animated ad, and a still picture of Bowser. The rails with scrolling neon arrows have been redesigned into neon rails with light arrows on top of them.

The course layout is roughly the same, but with a few changes. A drop-off has been added at the entrance to the tunnel, the U-turn near the end has been modified into an anti-gravity section, while the water puddles in that section are removed, and the air current found near the S-Bend has been moved to behind the banner, instead of beside it. The music is also roughly the same, similar to 3DS DK Jungle and  Wii Grumble Volcano, but an electric guitar has been added. Bowser's minions - Paratroopas, Dry Bones, Hammer Bros., Fire Bros., and Boomerang Bros. - are spectators for this course. In addition, like in the rainy courses in Super Mario 3D World, rain drops flow down the screens of both the GamePad and the TV, just to add minor effect.

Trivia

 * Despite being a Bowser-themed track, Bowser himself is not the Staff Ghost for either of the track's appearances. It is one of the few Bowser-themed tracks with this trait.
 * Some of the buildings found in this course are based on the dome hills from the grasslands in the mainstream Mario games.
 * In Mario Kart 8 the signs display the text "Neo Bowser City" even in PAL regions where the name of the course is "Koopa City". This is the same in 3DS Music Park (called "Melody Motorway" in PAL regions).
 * This track is one of three courses in Mario Kart 8 where the starting banner can be interacted with from playable characters via hang-glider. The other two courses are Mario Circuit and DS Wario Stadium.
 * However, the banner for this track spins when hit, whereas the other aforementioned track's banners only swing.
 * At a certain part in the track, a spotlight with Bowser's emblem is pointing to the sky, very likely referencing the Batman spotlight (called the "bat signal") in the Batman series.