The Stone from the Sky
At the center of the universe lie the twin worlds of Abeir and Toril, slightly out of phase with each other. Both revolve around the same sun and both have a large lunar satellite, Selune, trailed by a line of moon-lets know as the Tears of Selune.
Toril is the body that folk refer to as “the world.” In the aftermath of the Spellplague, it includes pockets of Returned Abeir that have replaced pockets of the old Toril. The planet’s primary and “central” continent is Faerun. To the north of Faerun is the artic north, home to the polar icecap. To the west of Faerun is the Trackless Sea, and beyond that horizon lies Returned Abeir, which completely replaced a land known as Maztica. To the south of Faerun is the Great Sea. To the east of Faerun are the Hordelands. Other continents exist as well, but the folk of Faerun and Returned Abeir know little about those far-off lands.
Most cultures of Faerun follow the Calendar of Harptos, named for the long-dead wizard who invented it. The Faerunian year is 365 days long, marked by the passage of Toril around the sun. The year is divided into twelve months of thirty days, loosely coinciding with the waxing and waning of Selune, and five annual holidays. In lieu of weeks, each month is divided into three tendays, also known as rides. Once every four years, Shieldmeet is added to the Calendar of Harptos as a “leap day” immediately following Midsummer night.