Atlantis is a free open-ended multi-player computer moderated fantasy turn-based strategy game for any number of players.
There is no declared winner of the game, players set their own objectives, and one can join at any time.
Russell Wallace developed the initial version and ran the first game, Atlantis 1.0 in 1993.
In 1999 Atlantis 4.0 was created by Geoff Dunbar and released under terms of GNU GPL.
"AtlantisDev" Yahoo Group was formed sometime after that and Joseph Traub became the maintainer of the code.