Windy Valley

Windy Valley (ウィンディーバレー) is one of the action stages featured in Sonic Adventure.

It is located in the Windy Cave in the Mystic Ruins. The area can only be accessed by using the Wind Stone to unblock the wind currents that lead to the stage. The level is split into three main parts: the windy hills at the beginning, the tornado, and the aerial spiraling tracks. Sonic goes through all three, while Tails goes through only the third, and Gamma goes through only the first.

Sonic
In Sonic's story, Windy Valley is the second level. Here, he and Tails attempt to track down a Chaos Emerald to stop Chaos from collecting them all.

Tails
Windy Valley is Tails's first level, where he must race Sonic to the Chaos Emerald at the end. Interestingly, because the whole level moves downward, Tails can fly from the beginning to the end of the level without touching the ground.

E-102 Gamma
Windy Valley is Gamma's third level. Here, Gamma searches here for E-103 Delta to free him after the Egg Carrier crashed. Like his other levels, enemies and other structures must be destroyed to increase the time limit.

Mario and Sonic at the London 2012 Olympic Games
In this game, Windy Valley is the location where the dream discos event takes place. The characters must collect rings and avoid obstacles.

Trivia

 * In the Sonic X episode "A Chaotic Day", Sonic and Tails head to what appears to be Windy Valley in search of a Chaos Emerald.
 * The music in the Windy Hills section of Windy Valley is based on the Special Stage music from the Mega Drive version of Sonic 3D Blast. The aerial tracks area has music based on Green Grove Zone Act 1 from the same game.
 * Windy Valley will be a playable stage in Mario & Sonic at the London 2012 Olympic Games.