[3] From May 8 to October 9 in 1988, daylight saving time was tested to better accommodate the calendar of competitions held during the 1988 Summer Olympics in Seoul.
It is likely that Koreans used water clocks to keep time prior to this invention, but no concrete records of them exist.
[6] In 1437, Jang Yeong-sil, with Jeong Cho, created a bowl-shaped sundial called the angbu ilgu (앙부일구), which King Sejong had placed in public so anyone could use it.
[7] Geographically, the western parts of Korea, including the South Korean capital city, Seoul, are GMT+08:00.
[8] In order to accommodate American television viewers, South Korea observed daylight saving time (GMT+10:00) when Seoul hosted the 1988 Summer Olympics.