Twinkle Park

Twinkle Park (トゥインクルパーク) is an action stage in Sonic Adventure and Sonic Adventure DX.

Overview
The stage is based off of a theme park, and every part of it is designed to give off a magical feel, with neon lights and sparkly objects everywhere. This stage is playable as Sonic, Amy, and Big.

After being shot down in the Tornado, Sonic is looking for Tails when Amy finds him, and follows him to Twinkle Park, where she gets excited when she notices a sign stating that "cute couples can get in free". She instantly enters the park, much to Sonic's dismay, who is forced to chase after her.

Big's reason for coming to Twinkle Park was that he followed Froggy there, and must try to catch him in the pool in the park.

Sonic
Sonic starts out on a race track with enemies driving bumper cars around. Sonic must defeat an enemy and steal it's bumper car, then take to the track. After this area, Sonic jumps in a roller coaster, then proceeds to run through a variety of amusement park obstacles built around a castle.

Amy
Amy starts out by the large swimming pool where she must push three buttons to proceed. Afterwards, she heads into the castle, which turns out to be a giant house of mirrors. Afterwards, she proceeds through a short section of Sonic's level before finishing.

Big
Big also starts out in the giant swimming pool area, where he is tasked with catching Froggy. The area is very small, and there aren't many fish here, which can make catching large fish for Big's "B" and "A" rank missions somewhat difficult.

Trivia

 * Outside Twinkle Park, there is a sign that says "Twinkle Park: Cute couples get in free".
 * The music in the first section of this level is a remix of the Panic Puppet Zone (Mega Drive version) music from Sonic 3D Blast. It is also the music played at the beginning of Sonic 3D as well.
 * When riding on a bumper car, the car speeds up and accelerates faster the more rings you collect, eventually capping out at 99. Collect large amounts of rings is essential if you want to go fast!
 * After a certain point, on the grass triangle outside Twinkle Park, the Cart Pass becomes available for all characters. This allows characters not otherwise available (a.k.a Tails) to participate in the bumper car section.
 * Tails, Knuckles, and E-102 Gamma can also get into Twinkle Park through the use of glitches and/or debug mode. They will start in the bumper car's section, however the game will put them in an area below the starting point, falling into a bottomless pit forever. If Knuckles or E-102 glides/hovers long enough, they will eventually find the track and can proceed into the level (Tails can't do this, as his flying ability doesn't last long enough).
 * In Sonic's stage, a major short cut can be found right after the roller coaster section. By holding left as you are ejected from the coaster, you won't fall down the hole. You can then run backwards and fall off the edge, landing on a hidden platform. From here, you can Spin Dash to the swimming pool, thus skipping a large portion of the stage. This helps immensely with Sonic's A-rank mission.
 * This is the only level in Sonic Adventure where there is an entire area where Sonic can't access in an area he is playable (aka the House of Mirrors accessible only by Amy).