The Known World of Firma consists, broadly speaking, of two continents and several islands and island chains. A mystical phenomenon known as the Pale encloses the Known World, preventing travel into or out of it. The total surface area of the Known World is roughly 28 million miles, and it forms an oval or oblong shape, being considerably wider than it is tall, with respect to the poles. It is understood that the Known World is more northerly than southerly, based on the proximity of the poles, and its central point lies closer to one continent than the other, making it seem to be more easterly than westerly from the perspective of most civilizations and peoples.
The two major continents of the Known World are Kaht and Athene, but there is also the proposed continent of Egatha. The population of the Known World is estimated to be somewhere close to 200 million people, and most of those live in Kaht. There are a variety of intelligent species that inhabit the Known World, the most populous of which are humans.
It is unclear how old the Known World is, nor when exactly it was cut off from the rest of Firma, but the earliest recorded histories date back a little over 2,000 years. It is known, however, that civilizations existed in the Known World prior to this, based on recent archeological finds in Athene. The current year by most standards is 638 FF, reckoned by the imperial calendar of Old Altisia.
Climatically speaking, the Known World predominantly consists of arid, semi-arid, and Mediterranean regions. Kaht is considerably more arid than the rest of the Known World, with much of its landmass consisting of the massive hot desert known as the Blistering Sea. Athene is, by contrast, considerably more wet and cold, with a great deal of its interior falling into the temperate zone, and being dominated by forest. The southernmost reaches of the Known World, near Egatha and Palissa, bizarrely ranges from tropical to arctic, and indeed, near the edges of the Pale these kinds of major climatic distortions are regular.