Sky theme

Stages with a Sky theme typically have Clouds, Large Drops and sometimes the Tornado. These Stages are usually taking place on a flying fortress built by Doctor Eggman.

Its first appearance was in Sky Base Zone from Sonic the Hedgehog (8-bit) which is the last zone of the game. However the game wasn't very popular so most people think of Sky Chase Zone from Sonic the Hedgehog 2 as the first Sky themed level.

Stages with A Sky Theme

 * Sky Base Zone, Sonic the Hedgehog (8-bit) (1992)
 * Wing Fortress Zone, Sonic the Hedgehog 2 (1992)
 * Sky Chase Zone, Sonic the Hedgehog 2 (1992)
 * Stardust Speedway, Sonic CD (1993)
 * Launch Base, Sonic the Hedgehog 3 (1994)
 * Sky Sanctuary, Sonic & Knuckles (1994)
 * Sky Chase, Sonic Adventure (1999)
 * Sky Deck, Sonic Adventure (1999)
 * Labyrinth of the Sky, Sonic Labyrinth (1995)
 * Sky Chase, Sonic Pocket Adventure (1991)
 * Aerobase, Sonic Pocket Adventure (1991)
 * Egg Rocket Zone, Sonic Advance (2001)
 * Sky Rail, Sonic Adventure 2 (2001)
 * Sky Canyon, Sonic Advance 2 (2002)
 * Egg Fleet, Sonic Heroes (2003)
 * Altar Emerald, Sonic Advance 3 (2004)
 * Glyphic Canyon, Shadow the Hedgehog (Game) (2005)
 * Sky Troops, Shadow the Hedgehog (Game) (2005)
 * Air Fleet, Shadow the Hedgehog (Game) (2005)
 * Altitude Limit, Sonic Rush (2005)
 * Crisis City, Sonic the Hedgehog (2006) (2006)
 * Sky Park, Sonic Rivals (2006)
 * Sky Babylon, Sonic Rush Adventure (2007)
 * Tornado Defense, Sonic Unleashed (2008)
 * Sky Sanctuary (Sonic Generations) (2011)