From the frontpage of the module:
Years ago a sailing ship mysteriously appeared inland on the busy trade route into the Wild Coast towns. It was quickly turned into a way-station. Not long after, the Pomarj pushed north and trade dropped to a trickle. Nowadays only a few desperate souls are willing to brave this rainy night in the name of the Greyhawk Guilds. A one-round Core adventure set in the Domain of Greyhawk for characters level 1 - 15 (APLs 2 - 12).