Have you heard of this festival yet? I doubt it. First it is going to be this Saturday May 21st starting from 10:30 until 16:00 at the Guchae Bosang park (국채보상운동기념공원) It's the park with the huge bell. There will be over 15,000 people participating in this festival, there is going to be over 80 booths and a number of events going on throughout the day. There is going to be an award ceremony for the people who have given a lot to the community. There is a lot of different foods, games, performances and many arts and crafts booths that will be there. Almost all of the booths are free so you don't have to worry.
Key points of this festival.
10:00 starts the award ceremony
If you just want to watch the performances that starts at 11:30 until 16:00.
Check the map below if you don't know where it is :)