During most of the Joseon Dynasty, Korea was divided into eight provinces (do; 도; 道). The eight provinces' boundaries remained unchanged for about 480 years from 1413 to 1895, and formed a geographic paradigm that is still reflected today in the Korean Peninsula's administrative divisions, dialects, and regional distinctions. The names of all eight provinces are still preserved today, in one form or another. These eight historical provinces form both North and South Korea, and are not to be confused with the provinces that make up South Korea or North Korea.
In 1413 (the 13th year of the reign of King Jeongjong), the northeastern boundary of Korea was extended to the Tumen River. The country was reorganized into eight provinces: Chungcheong, Gangwon, Gyeonggi, Gyeongsang, Jeolla, P'unghae (renamed Hwanghae in 1417), P'yŏngan, and Yŏnggil (eventually renamed Hamgyŏng in 1509).
For almost 500 years, the eight-province system remained virtually unchanged. In 1895 (the 32nd year of the reign of King Gojong), the five-century-old provincial system was abolished. On May 26 of that year—as part of the Gabo Reform—the country was redivided into 23 districts, each named for the city or county that was its capital.
(Each district name in the following list links to the article on the province from which the district was formed, and where more detailed information on the district is provided):
Andong
Chuncheon
Chungju
Daegu
Dongnae
Gangneung
Gongju
Haeju
Hamhŭng
Hanseong
Hongju
Incheon
Jeju
Jeonju
Jinju
Kaesŏng
Kanggye
Kapsan
Kyŏngsŏng
Naju
Namwon
P'yŏngyang
Ŭiju
Provinces of KoreaSpecial cities of North KoreaSpecial cities of South KoreaAdministrative divisions of South Korea and Administrative divisions of North Korea
The new system of districts did not last long, however, as one year later, on August 4, 1896, the former eight provinces were restored, with five of them (Chungcheong, Gyeongsang, Jeolla, Hamgyŏng, and P'yŏngan), being divided into north and south halves, to form a total of 13 provinces.