Korea National League

The Korea National League was a semi-professional football league, the third tier of the South Korean football league system. It was held from 2003 to 2019.
History.
The league was officially founded in 2003 as the K2 League to raise the level of competition in Korea. Prior to that, Korean National Semi-Professional Football League was run by the governing body of semi-professional football. Competitions under the present body can be traced back to 1964, with the participants being mostly work sides of the major industries in Korea (banks, construction companies and the like). It was rebranded as the Korea National League at the beginning of 2006.
It had operated with a two-stage season since its inception, with the two-stage winners meeting in a two-legged championship playoff final at the end of the season before changing to a four team playoff in 2008.
At the end of 2019, the Korea National League was absorbed into the K3 League after the final season was finished.
Promotion issue.
Ever since the creation of the league, hopes had been high that a system of promotion and relegation would be implemented between the league and the K League, the professional football league in Korea. In 2006, it was agreed that, subject to meeting certain financial requirements, the National League champions would be eligible for promotion. Goyang KB Kookmin Bank, who triumphed over Gimpo Hallelujah to win the 2006 title, were the first side eligible for promotion; however, they controversially rejected the chance to return to the professional ranks. The team received several threats from the National League ranging from being thrown out of the competition, to fines, to point deductions for the upcoming 2007 season. In the end, the side received a point deduction penalty, to be split into ten point deductions in the first and second stages of the 2007 season.
Following the case involving Goyang, teams in the National League signed agreements indicating whether or not they would seek promotion to the K League if they won the National League in 2007. Hyundai Mipo Dockyard, who won the championship in 2007, also rejected the chance to move up to the K League despite previously indicating they would seek promotion. In light of the issues surrounding the conditional promotion place in 2006 and 2007, the National League decided to end the system prior to the 2008 season.
All-time clubs.
There have been a total of 16 member clubs since the league was founded as the "K2 League" in 2003. Seoul City replaced Iksan Hallelujah for the second stage of the 2003 season after protests by radical Wonbuddhists forced the Christian club out of Iksan. Hallelujah FC returned to the league in 2004 after moving to Gimpo. Icheon Sangmu, essentially the reserve side of K League team Gwangju Sangmu, withdrew from the league at the end of 2005 in order to compete in the Reserves League. In the 2010 season, Nowon Hummel moved to Chungju city in Chungbuk province, and the club's name changed to Chungju Hummel.
Clubs in bold are founding members of the K3 League.