South Korea

Like many other harvest festivals around the world, Chuseok is held around the autumn equinox, i.e. at the very end of summer or in early autumn. It is the biggest traditional holiday in South Korea. It is three day holiday in South Korea and celebrated for one day in North Korea. (Wikipedia)

Hangul Day is a national Korean commemorative day marking the invention of the Korean alphabet by the 15th-century Korean King Sejong the Great. (Wikipedia)