Ancient star maps are three-dimensional representations of the universe as known to the Ancients.
The databases of many, if not all, Ancient ships contain one, as well as any outposts once inhabited by them. Praclarush Taonas and Terra Atlantis are included on the map. In addition to Taonas and Earth, the map probably contains all known planets in the Alteran Home Galaxy, the Milky Way, and Pegasus, as well as any other galaxies the Ancients visited. The star maps also contain Stargate addresses for every planet which the Ancients put a Stargate on. (SG1: "Lost City, Part 2", "The Pegasus Project", SGA: "Rising")