Marinepia Nihonkai

Marinepia Nihonkai is the name of Niigata City's aquarium.  It's not as big or flashy as some of the other aquariums in Japan (Okinawa's Churaumi Aquarium is amazing!), but Marinepia is still a lot of fun for kids, especially on a rainy day (Niigata has a lot of those).

Their website has a good amount of information in English, as well as a number of other languages, and there are multilingual maps and guides available at the entrance.  In addition to the varieties of fish, seals, and penguins, there is a dolphin show several times a day, as well as an area for children to touch starfish, sea cucumbers, and hermit crabs.

The annual passport prices are very reasonable, especially for children, and passport-holders can get a 10% discount at the aquarium restaurant on the top floor.  If you'd prefer some non-Japanese food, Havan Dining, an excellent Indian vegetarian buffet, is right across the street.

Marinepia Nihonkai Aquarium: http://www.marinepia.or.jp/mlg/en