South Korea is divided into 17 top-level administrative subdivisions including 1 special city, 1 special self-governing city, 6 metropolitan cities, 8 provinces, and 1 special self-governing province. Seoul is the capital and largest city located in the northwest. Sejong is a planned city in the center that hosts many government agencies and was proposed to become the new national capital. The provinces and metropolitan cities cover most of the mainland while Jeju is a popular island province located 130 km south of the mainland.