Places to See with the Kids: COEX Mall
COEX is a fairly new U.S.-style shopping mall, enclosed for all-weather fun. There is the usual shopping, and a food court with both Korean and “Western” food (pizza, burgers).
The real attraction is a very nicely done aquarium (admission charge). The aquarium is themed, meaning you explore zones such as “Deep Sea”, “Tidal Pools”, “Amazon Rain Forest” and the like. Go on a weekday if possible to avoid awesome crowds. The place has a h-u-g-e shark tank, giant rays and whole schools of tropical fish.
There is a fairly lame kind of fishy petting zoo, which will only appeal to pretty young children—our nine year old was bored within minutes, while our five year old was reasonably entertained (Note for parents: someone used their head, installing sinks with soap and water right near the petting area to rinse off all the aquatic scum kids will acquire fishing around).
COEX is too far from downtown for a taxi; take the Green subway line to SAMSUNG station. If you follow the somewhat-vague exit signs correctly, you get up into the mall without even going outside.