The solar system today called the Pact Worlds has been inhabited for millennia, stretching back tens of thousands of years even before the Gap. While all of the planets in the system could make an argument for their own significance, most outside observers agree that the system's most important planet was the third from the sun, called Golarion.
The presumed birthplace of humans, dwarves, halflings, and numerous other races still found in the system, Golarion was most notable not for its vast civilizations, but its theological significance: in addition to caging a dark god of destruction called Rovagug in its core, Golarion was also home to a magical object called the Starstone, which allowed mortals to ascend to godhood. At some point during the Gap, however, that world vanished. High priests and divine servants petitioned their gods for answers, and all received the same information: Golarion still exists, as do the descendents of those people on it when it vanished, safe in a seclusion unreachable by magic or science. Beyond that, gods and demons all maintain the same firm policy that no further information will be forthcoming—if indeed they even know it. The existence of Absalom Station in Golarion’s former orbit raises even more questions. Was it built as a lifeboat? Was it simply a Golarion-made space platform left behind after the disappearance? Or was the station itself somehow responsible for the planet’s disappearance? Regardless, the mystery of Golarion leads many both within and without the Pact Worlds to still refer to the solar system as “the Golarion System.”