SEGA Carnival is is a racecourse in Sonic Riders. Not part of the game's main Story Mode, the track features simply as an extra level for Free Play, although there are 5 tasks to complete in Mission Mode too. It is unlocked by earning a Gold Emblem in the Heroes Cup in Grand Prix Mode.
A cross-franchise smörgåsbord of SEGA gaming, the Carnival starts off in a Samba de Amigo-themed Mexican street party, before the racers pass through (in sequence): the pirate ship from Billy Hatcher and the Giant Egg's Pirate's Island, a Nightopian castle from NiGHTS into Dreams, tilting bowling greens from Super Monkey Ball, and high-rise city streets from Crazy Taxi. Hidden behind a sign at the entrance to the city area is Crazy Taxi's Axel himself, who will give the player a taxi ride as a convenient shortcut!