from the introduction:
Hargrave's Tavern is an adventure module compatible with the D20 system. No ancillary books are needed other than the materials found for free at http://www.d20srd.org/ . Unique characters, maps, treasures, etc are all provided and detailed in this module. However, inexperienced players should obtain and use a copy of the Dungeons and Dragons® 3rd Ed. or Pathfinders® Player's Handbook before playing.
This module was particularly designed as the first installment of the campaign series titled Wrath of the Morning Star for a good mix of classes and characters starting at level 1 above neutral alignment. However, this module can easily be used for any good beginning party totalling three or more 1st level characters as a generic starting point for any campaign.
from the Adventure Summary:
A visiting Paladin named Lathos, had recently been given orders to commission a low-level expedition of adventurers into the unexplored lands of Yaog to investigate the source and origin of a mysterious flier. Accordingly, he has summoned the PCs to meet him at the Gleim City Ruins Citadel. This strange flier, containing 12 different language translations, is advertising for miners and surveyors with a unique set of skills offering more than a generous amount of pay. It has recently been posted at Gleim city ruins. Oddly it does not have a place or time written on it.