Faerûn is a fictional subcontinent, the primary setting of the Dungeons & Dragons worl of Forgotten Realms. It is the western part of an unnamed supercontinent quite similar to real-world Afro-Eurasia. It is set on the planet Toril (more formally, "Abeir-Toril"). Other parts of this supercontinent include Kara-Tur (original setting of the D&D Oriental Adventures campaign setting), and Zakhara, home to the Arabian Nights setting Al-Qadim. Maztica, home of a tribal, Aztec-like civilization is far to the west, across the Trackless Sea. The subterranean regions underneath Faerûn are the Underdark.