The construction of planned cities started in the 1970s. The industrial functions of Seoul were relocated to Banwol New Industrial City (Ansan-si today). Yeocheon-si for the Yeocheon Industrial Complex and a hinterland city for the Changwon Industrial Complex were planned. Gwacheon-si was planned as the 2nd government complex to relocate the central government’s administrative functions. In the 1980s, Daedeok Research and Academy City (Daedeok Research and Science City today) was planned to develop Korea’s sciences and technology. New towns were also constructed as hinterlands to support newly built industrial complexes.

In the late 1980s, the First New City Plan of the Seoul Metropolitan Area was initiated to respond to the rapid increase in housing prices in Seoul. As a result, five new large-scale residential cities, including Bundang, Ilsan, Pyeongchon, Sanbon, and Jungdong, were developed. These new cities greatly contributed to the metropolitanization of the Seoul Metropolitan Area. In the 2000s, according to the Second New City Plan, more new cities were built in the Seoul Metropolitan Area. At the same time, innovation cities were built beyond the Seoul Metropolitan Area to achieve balanced national development by relocating public administrative agencies and research institutes to these innovation cities. By 2020, the third set of new cities in the metropolitan area was planned and is currently under construction.