The central feature of the Sumida Aquarium is the 350,000-liter tank, the largest indoor tank in Japan, which is home to dozens of penguins and seals. The glass walls are so thick that they require no additional supports, so that visitors can admire the creatures from virtually any angle. The design of the tank allows you to get right up close to them, thanks to the walkways and other structures positioned above the surface of the water.
