a.k.a. The Empty City
Location of the nightmare chase at the beginning of Chapter 1. Full of yellow fog. Gray brick walls tower overhead above where the fog thins. The walls sag in at uncomfortable angles. Distant buildings seem domed or arched, empty, or not. Streets of broken cobblestone below, and an oily purple moon bruises the sky above.
Ray had a brief vision of this city during his nightmare in Chapter 6.
Dora saw charcoal sketches of what she thought might be this city, presumably made by Ulver Zandalus, in her psychometry vision of Dr. Losandro’s office in Chapter 22.
In Chapter 39, the party tied the appearance of the star stelae to the look and feel of this place, and believed that they were all linked somehow to Hastur.
They discovered later that same chapter that this city was being depicted in charcoal and yellow chalk on the walls of houses in Thrushmoor.
In Chapter 43, the party recalled the name of the city: Carcosa, and they thought of it as where Hastur either lives or rules or is imprisoned, and the place to where Xhamen-Dor drags the worlds it conquers.
During the botched “Great Harvest” ritual in Chapter 51, Carcosa was briefly viewed as co-existing with Thrushmoor. In the Carcosa-version of Thrushmoor, Iris Hill was absent, replaced by a windowless tower with battlements. Upon seeing the city, all (who hadn’t already) immediately knew its name.
In Chapter 61, Rony recalled some of its history:
According to ancient legends and whispered myths, the human civilization that first made contact with Hastur existed long before humanity eventually rose on Golarion. In a distant time, on a distant world whose name has been long forgotten, three great cities ruled from three different shores of the vast Lake Hali: Yhtill, a place ruled by and for the aristocracy; Alar, a home of anarchists; and Carcosa, the empty city, built by unknown hands and abandoned by all. Carcosa was old and in ruins before people laid the first foundations of Alar or Yhtill, and those few who visited Carcosa’s empty streets returned mad and prone to self-destruction—if they returned at all.
One day long ago, the armies of Alar besieged Carcosa, hoping to harness whatever source of power that so fully emptied minds and ruined souls. By the next morning, the city of Alar and its population had vanished without a trace. Later, during a masked ball thrown by Queen Cassilda of Yhtill, a stranger appeared wearing a pallid mask. The stranger revealed to the queen that he wore no mask and had come to announce the end of Yhtill’s dynasty. Madness quickly swept through Yhtill, and with the dawn Yhtill vanished as well. Only the ghost city of Carcosa remained.
In Chapter 62, Dabwick revealed that they saw Carcosa in a painting in the home of Miacknian Mun several years earlier and that they had found the concept of it appealing.
In Chapter 74, while meditating for spells, Dabwick experienced a vision of the Conglomerate City that filled them with dread.
In the Act III Prologue, the party experienced a series of visions from Xhamen-Dor's impossibly long lifespan, which included flashes of events billions of years ago.
In Chapter 169, Dabwick’s friends Alyanna, Chet, and Sam were freed from their imprisonment in the city of Carcosa and had information about it to share based on their time spent there. Alyanna said:
Carcosa: do you have even the smallest grasp of how many towns, how many cities, and how many entire WORLDS are contained within it? It is infinite. You can travel from one “Nexus” to the next, passing through the streets of a city on one planet into the streets of a city on another, into an entirely other world. All around you, architecture and civilization from across the universe. It is bigger THAN a universe.
Sam continued:
Carcosa exists in ALL times.
We entered one “Nexus,” Alyanna and I, looked around for a few minutes, came back out and Chet was 30 years older.
Every “Nexus” exists by the rules of the planet it was stolen from. Magic works differently in every neighborhood. Time works differently in every neighborhood.
And about the forming of “Nexuses,” Sam indicated that:
When a nascent “Nexus” is formed, it exists outside of Time. You can’t enter it, and you can’t leave it—at least not by any means we know.
First Reference: Chapter 1
Other Notable References: Chapter 6, Chapter 22, Chapter 39, Chapter 43, Chapter 51, Chapter 61, Chapter 62, Chapter 74, Act III Prologue, Act III Interlude 1, Chapter 169, Chapter 175, Chapter 183