Atlantis is the name of an island appearing in the writings of Plato. Ancient Athens was supposedly able to repel attacks by Atlantis. The story concludes with Atlantis falling out of favor with the gods and submerging into the Atlantic Ocean.
The story is generally considered to be an invention by Plato, in order to illustrate his concept of an ideal state, but it has also been argued that he may have been inspired by earlier myths. Various locations and inspirations for Atlantis have therefore been proposed. Atlantis has also inspired later fictional and esoteric writings.