Tokyo Sea Life Park is a very impressive aquarium. Its mission is to display animals from Tokyo’s own sea and the rest of the world, and it has a wide range of exhibition areas. Highlights include a donut-shaped tank containing 2,200 tons of water housing bluefin tuna and a penguin park.  Make sure you ask a guide what time the penguin feeding times are.

A trip can be combined with a stroll or picnic in Kasai Rinkai park and a ride on the nearby giant Ferris wheel.

Luckily for cheapos there are three days a year that allow free admission: October 10th (The aquarium’s Anniversary Day), May 4th (Greenery Day), and October 1st (Tokyo Citizens’ Day).