The track starts the racers at the entrance of the park. The racers go straight up some stairs to enter the ride with a right turn. Going on this path until the jump into water. One side is a boost and has the player go farther.
This portion is an anti-gravity section with a submarine-styled cart for the ride.It travels at a steady pace so racers can hit into it to get a speed boost. The racers now travel in a loop out of the water and back into it ending the anti-gravity section.
The course goes through a bend around a carousel that can boosted through with a mushroom or star. Upon exiting the water, there is a gliding ramp that launches the racers towards the finish line. Inbetween, there is the ticket booth and a ferris wheel. The ferris wheel's cars can get in the way of gliding racers, slowing them down. In higher speeds, it is possible to ride on top of the ticket booth instead of going around it.
Trivia[]
The map of the course is seen on some billboards around the course, likewise with Rainbow Road and GCN Yoshi Circuit.
In 200cc, it is possible, along with Wii Grumble Volcano and others that have a gliding pad before the checkered banner, to hit the finish line banner if one has the right combination of kart and character. But unlike Mario Circuit, DS Wario Stadium, and 3DS Neo Bowser City, it does not interact with the player.
Posters in the entrance for the Sub Coaster show the structure of the Sub Coaster cars, the structure of a Mecha Cheep and the height requirement for the ride (being taller than a Goomba).
The History of the Submarine posters say the first generation model was manufactured in 1987. 1987 was the year Famicom Grand Prix: F-1 Race was released; the first racing game to feature Mario characters.
This course appears on some of the posters for the sponsor Galaxy Air.