From the Super Mario Wiki
Pac Labyrinth is a racecourse in Mario Kart Arcade GP and Mario Kart Arcade GP 2; it serves as Pac-Man and Blinky's second racecourse. This racecourse starts out in Pac-Land, but after the player drives the character into the cave and comes out, the course looks like the maze of the original Pac-Man game.
The background is dark with flying Pac-Man and ghost sprites. The dots that Pac-Man eats in the original Pac-Man game appear through this course as well. After a while, the player drives back in Pac-Land, and after driving through Pac-Land for a little while, the player enters back in the maze-like level.
There are many platforms that can be used for jumping shortcuts.