The 3rd International Undergraduate Mathematics Summer School is sponsored by the Department of Mathematical Sciences, Seoul National University. The partner universities are Moscow State University, Peking University and the University of Tokyo. The Summer School intends to cover some fundamental aspects of modern mathematics, and invite undergraduate students to more advanced topics that are not covered by the standard curriculum.
The first International Undergraduate Mathematics Summer School was held at Peking University in 2018.
https://www.math.pku.edu.cn/misc/puremath/summerschool/index.htm
The 2nd International Undergraduate Mathematics Summer School was held at University of Tokyo in July 2019.
http://park.itc.u-tokyo.ac.jp/MSF/UGMSS/