This is my list so far:
South Island
~ From Sonic the Hedgehog (16-Bit) ~
- Green Hill Zone
- Marble Zone
- Spring Yard Zone
- Labyrinth Zone
- Star Light Zone
- Scrap Brain Zone
- Bridge Zone
- Jungle Zone
- Underground Zone
- Sky High Zone
- Green Hills Zone
- Aqua Lake Zone
- Gimmick Mt. Zone
- Scrambled Egg Zone
- Crystal Egg Zone
- Turquoise Hill Zone
- Gigapolis Zone
- Sleeping Egg Zone
- Mecha Green Hill Zone
- Aqua Planet Zone
- Electric Egg Zone
- Great Turquoise Zone
- Sunset Park Zone
- Meta Junglira Zone
- Robotnik Winter Zone
- Tidal Plant Zone
- Atomic Destroyer Zone
- Yellow Desert Zone
- Blue Marine Zone
- Red Volcano Zone
- Silver Castle Zone
- South Island/Canyon Cruise
- Station Square - Twinkle Park/Casinopolis/Speed Highway
- Emerald Coast
- Mystic Ruins - Lost World
- Final Egg
- Central City - City Escape/Mission Street/Radical Highway
- Route 101/Route 280
- Wild Canyon/Dry Lagoon
- Pumpkin Hill/Sky Rail/Aquatic Mine
- Sand Ocean - Pyramid Cave/Hidden Base/Egg Quarters/Death Chamber
- Green Hill Zone - Emerald Town/Emerald Beach
- Central City - Library/Battle Highway
- Night Babylon - Club Rouge/Gimme Shelter
- Central City - Westopolis/Lethal Highway
- Leaf Storm Zone
- Mirage Road Zone
- Water Palace Zone
- Night Carnival Zone
- Huge Crisis Zone
- Blue Ridge Zone
- Station Square (?)
- Metropolis (?)
* South Island is the homeland of Sonic as he grew up. This is where both "Sonic 1" for the Genesis and GameGear take place, and the GameGear version of the game features a map of the island.
* "Sonic 2" for the GameGear features a similar-looking zone titled "Green Hills Zone", hinting that it's the same zone. Likewise, Mecha Green Hill Zone in "Sonic Chaos" is a roboticized version of Green Hill Zone created by Dr. Eggman. South Island and Canyon Cruise in “Sonic the Fighters” also take place near Green Hill Zone, as evidenced by their similar appearances and in-game description. Green Hill Zone itself reappears in "Sonic Blast", SA2, "Sonic Battle", and "Sonic Chronicles".
* The location for "Sonic Triple Trouble" is a bit vague, but it's hinted to be South Island due to the emeralds splitting across "the island". Some have argued that it could also be Angel Island since Knuckles is included in the game, but it's most likely the former since Sonic is shown to be living there.
* Station Square, Mystic Ruins, and Central City are all revealed in “Sonic Battle” and “Sonic Chronicles” to take place on the eastern side of South Island, thus placing the events of SA1, SA2, “Sonic Battle” and “Shadow the Hedgehog” on the island. Likewise, Emerald Town is Sonic's hometown and it takes place near Green Hill Zone.
* Leaf Storm Zone is located near Tails' workshop in “Sonic Rush”, so it could take place in the jungles surrounding the Mystic Ruins.
Factors
* Metropolis Zone is shown to be located on South Island in “Sonic Chronicles”, when it's actually located on Westside Island. Whether or not it's the same Metropolis Zone is anyone's guess.
Westside Island
~ From Sonic the Hedgehog 2 (16-Bit) ~
- Emerald Hill Zone
- Chemical Plant Zone
- Aquatic Ruin Zone
- Casino Night Zone
- Hill Top Zone
- Oil Ocean Zone
- Mystic Cave Zone
- Metropolis Zone
- Wood Zone
- Dust Hill Zone
- Winter Hill Zone
- Dark Valley
- Desert Road
- Iron Ruin
- Rainy Savanna
- Quake Cave
- Balloon Panic
- Emerald Ocean
- Milky Way
- Training Area
- Ruin Wood
- Rail Canyon
- Metal Island
- Dark Castle
- Sea Gate/Seaside Hill/Ocean Palace
- Grand Metropolis/Power Plant
- Casino Park/BINGO Highway
- Rail Canyon/Bullet Station
- Lost Jungle/Frog Forest
- Hang Castle/Mystic Mansion
* Westside Island is the homeland of Miles “Tails” Prowler and the location for the events of “Sonic 2”. * “Sonic Drift” shares many zones from “Sonic 2” as well as several new zones, hinting it all takes place on Westside Island.
* “Tails' Sky Patrol” takes place either before or after “Sonic 2”, but the zones featured show many similarities to the zones seen in “Sonic 2”. This could very well take place on Westside Island.
* The location for “Sonic Heroes” is never revealed, but it's most likely Westside Island due to Rail Canyon sharing the same name as Rail Canyon from “Tails' Sky Patrol”. Likewise, Grand Metropolis shares its name with Metropolis Zone and sports many similarities to Chemical Plant Zone. Same goes for Casino Park and Casino Night Zone.
Angel Island/Onyx Island
~ From Sonic the Hedgehog 3 & Knuckles ~
- Angel Island Zone
- Hydrocity Zone
- Marble Garden Zone
- Carnival Night Zone (?)
- Ice Cap Zone
- Launch Base Zone
- Mushroom Hill Zone
- Flying Battery Zone
- Sandopolis Zone
- Lava Reef Zone
- Hidden Palace Zone
- Sky Sanctuary Zone
- Azure Lake Zone
- Balloon Park Zone (?)
- Chrome Gadget Zone
- Desert Palace Zone
- Endless Mine Zone
- Windy Valley
- Red Mountain
- Ice Cap
- Sand Hill
- Angel Island Zone
- Sky Canyon
- Chaos Angel
- Altar Emerald
- Holy Summit - Chao Ruins
- Forest Falls Zone
- Colosseum Highway Zone
- Sky Park Zone
- Crystal Mountain Zone
- Death Yard Zone
* Angel Island is a ancient floating island in the sky and the homeland of Knuckles the Echidna and the Master Emerald. It's the main setting of “Sonic 3 and Knuckles”, and made brief appearances in SA1, the “Sonic Advance” series, and “Sonic Battle”.
* In Silver's future, Angel Island sank to the planet's surface and became Onyx Island; the main setting of “Sonic Rivals".
Factors
* It's unknown if Carnival Night Zone and Balloon Park Zone actually take place on Angel Island. They never show up on the island overhead view and feel out of place. Since Angel Island crash-landed off the coast of South Island in both “Sonic 3 and Knuckles” and SA1, it's possible that these zones were located somewhere near Angel Island's impact zone. This could explain the similarly-named Night Carnival Zone in “Sonic Rush”.
What do you guys think? Let me know of your ideas or theories.














