10. Gwangju Songjeongjang (3.8 jang) - This is the largest market in the Jeolla area.
11. Guryejang (3.8 jang) - This is the largest market in the Mount Jiri area. People come to buy and sell goods from as far as Hadong, South Gyeongsang.
12. Jangheung Saturday Market (open Saturdays) - This is a traditional market specializing in hanwoo, Korean beef.
13. Beolgyojang (4.9 jang) - This market sells fish from the sea near South Jeolla.
The article also directs readers to Hana Tour, which offers tours to each of the twenty markets they mentioned.
Five-day markets aren't that unique. According to the Market Management Support Center, also linked in the Joongang Ilbo article, there are 113 five-day markets in Jeollanam-do and Gwangju. You can find more information about 92 of the ones in Jeollanam-do on this NamdoKorea page. That's not including markets, like Gwangju's large Yangdong Market (양동시장), that are open every day.