Casterly Rock is a prominent castle and the ancestral seat of House Lannister in the fictional world of Westeros, created by author George R.R. Martin. Located on the western coast, it overlooks the Sunset Sea and is known for its impressive cliffs and rich gold mines, which have contributed to the wealth and power of the Lannister family. The castle is characterized by its towering stone walls and strategic position, making it a formidable stronghold. Casterly Rock is also home to various legends, including tales of its founding by Caster, a legendary figure in Westerosi history.