Summer and Winter Schools usually take place in Korea over a course of 4-6 weeks. The credits students gain during the course can often be used towards their degree at their home university.
[2022 YISS] Yonsei International Summer School
Program: 28. June - 21 Juli (4 weeks) OR
28. June - 04. August (6 weeks)
Early bird deadline: 24th of April
Deadline: 13th of May
More Info: HERE
[2022] SNU Summer School
Program: 27. June - 30. July 2022 (5 weeks)
Deadline: 28.05.2022
More Info: LINK