Suwon became a big city because of King Jeongjo of Joseon. He wanted to make Suwon the capital after he moved his father's tomb. Suwon's Hwaseong Fortress was also built then. Hwaseong has great value because some machines were used to build it. Jeong Yagyong, a great mechanic and scholar, made pulleys named Geojunggi and Nokro, which were used.