Golarion is the “main” planet of the setting. It orbits a yellow sun in the far reaches of the Universe. Third of eleven in orbit, this blue planet contains vast oceans and lush green lands, the perfect environment for countless cultures to thrive. Indeed, Golarion is the most populous planet in its solar system and its crater-scarred moon, Somal, fills its night sky. It is more than 50 million years old, at which point its environment was hostile to modern forms of life, and its landscapes were dominated by prehistoric beasts. Dragons joined such beasts in the planet's prehistoric ages from that period to approximately 1 million years ago. Serpentfolk and other non-human beings became predominant from that point until approximately -10000 AR, which marked the dawn of human communities.

Golarion sits at the center of a complex planar cosmology known as The Inner Sphere where it serves as the prison for Rovagug, the Rough Beast, a god of pure destruction who sought to devour the universe. The gods of all alignments banded together to lock him in the planet's core (the Dead Vault).

Golarion also houses the Starstone. The Starstone is a unique gemstone that was once part of a massive asteroid called the Aeon Star, which was shattered by the deity Acavna before it could strike Golarion. The Starstone pierced Acavna and fell to Golarion as a meteorite in -5293 AR. The Aeon Star's remnants struck Golarion in an event known as Earthfall,which destroyed many ancient empires, including Azlant, Thassilon, Koloran, and Ninshabur. It also created the Inner Sea and it ushered in the Age of Darkness. The Starstone now rests in the largest cathedral of the Ascendant Court, where anyone can take the Test of the Starstone to attempt ascension to godhood. In the ensuing ages, only three mortals are known to have succeeded in the task that Aroden created: Cayden Cailean, Iomedae, and Norgorber.

• Death of prophecy: Unlike many fantasy worlds, the “Chosen One” prophecies in Golarion no longer work. When the god of humanity, Aroden, was prophesied to return and lead a new golden age, the world prepared for it and then he died. Because prophecy is broken, “destiny” no longer exists. Many nations (like Cheliax or the Sarkoris Scars) are currently in chaos because the “guaranteed” future disappeared and many live in existential dread.

• Old Ways vs. New Ways: Golarion blurs the line between traditional fantasy and technology. While most of the world operates on medieval logic fueled by spells, certain regions are grappling with the literal wreckage of a high-tech galactic past or the birth of an industrial future. It is not uncommon to find a village of simple farmers just down the road from a wizard’s tower capable of planar travel. Also there are many ruins throughout Golarion filled with powerful artifacts. Adventurers are essentially “arcane archaeologists” trying to reclaim power that humanity lost during Earthfall.

• Gothic and Cosmic Horror: Gothic horror in Golarion is centered almost entirely in the nation of Ustalav. It focuses on the fear of what hides behind closed doors, the weight of ancient lineages, and the thin line between civilization and savagery. In Ustalav, the monster is often a person you know, or a curse you inherited. Vampires, werewolves, and flesh golems created by mad scientists inhabit the lands. Cosmic horror assumes that humanity and even the gods are insignificant specks. The influence of the Elder Mythos (Cthulhu, Hastur) is a palpable threat. Golarion is just one planet in a vast, uncaring universe filled with Great Old Ones that could blink and destroy the world.