skippy311
Contributor
Aqua Planet is a nice alternative to sea diving should the weather turn bad in Jeju.
I searched for Udo through some of the Korean search enginea but the reaults were vague. It may take more time to find specifics.
However, I did stumble upon the Engliah page for diving in Jeju's Aquarium, Aqia Planet. Could be an interesting dive:
Dive and Get Up-close to Multiple Species of Marine Animals at the Aqua Planet Jeju