For the first time, the secrets of past empires of the Forgotten Realms world are chronicled in one comprehensive sourcebook. For players, this book contains new options for characters wishing to delve into ancient ruins, including new feats, prestige classes, magic, and equipment. For Dungeon Masters, this book contains new material associated with ruins, including rules for how to build and sustain a ruin-based campaign, more than a dozen detailed adventure sites with maps, and new monsters and artifacts.