Atlantis

Atlantis (アトランティス) is a location in the Sonic the Hedgehog series. It was a fabled continent that once existed on earth.

History
Regarded as nothing more than a fable, Atlantis sank into the sea during an unknown event long ago. However, some ruins of it resurfaced when Flicky Island was created, becoming the island's Rusty Ruin Zone. These ruins would later be desecrated when Dr. Robotnik laid siege to the island.

Trivia

 * Atlantis and its backstory is based on the real-world continent mentioned in Greek legends.