King's Landing is the capital of Westeros and the Seven Kingdoms. It is situated on the Blackwater river on the spot where Aegon the Conqueror landed in Westeros to begin his conquest. The main city is surrounded by a wall, manned by a city watch known as the Gold Cloaks. Within the walls, the city's natural landscape is dominated by three hills, named after Aegon and his two sisters. Poorer smallfolk build shanty settlements outside the city. King's Landing is extremely populous, but rather unsightly and dirty compared to other cities. The stench of the city's waste can be smelled far beyond its walls.
The royal castle, called the Red Keep, sits on Aegon's Hill. The Keep holds the Iron Throne, the seat of the monarch. Aegon commissioned the throne's construction from the swords of his defeated enemies. According to legend, he kept the blades sharp because he believed that no ruler should ever sit comfortably. Centuries later, kings still cut themselves on the throne.
The city also holds the Great Sept of Baelor, where the Most Devout convene with the High Septon. It is the holiest sept of the Seven.
The slums of King's Landing are called Flea Bottom, where residents are so poor they regularly subsist on "bowls of brown", a mystery stew that can include the meat of rats and murder victims.
King's Landing has an estimated population of more than 500,000, as stated by Tyrion when he meets Oberyn Martell on his arrival to King's Landing. George R. R. Martin has also stated that the city is larger than Medieval London or Paris but smaller than Medieval Constantinople or Ancient Rome (each had a population of about 1,000,000).