The Osaka Aquarium is located at the edge of Osaka`s Harbor, in combination with a festival marketplace, also designed by CambridgeSeven. The exhibit content of the aquarium presents the vast Pacific using the powerful organizing metaphor of the Ring of Fire — a linear zone of volcanic and tectonic activity outlining the Pacific Basin, corresponding to rich habitats and communities of animals. Visitors to the aquarium follow a clockwise and downward spiral, through habitats from different climatic zones along the Ring of Fire: Japan, Alaska`s Aleutian Islands, California`s coast, Ecuador and the Coast of Chile, Antarctica, New Zealand, and Australia. As visitors descend through the 286,000 sf, 2.9 million gallon aquarium, they view each exhibit from levels above the water`s surface and below — where the walkway becomes a tunnel through water held back by clear acrylic walls. The core of the aquarium, around which visitors move is a vast tank hosting a variety of species of fish of the mid-Pacific. The biogeographical plan of the building, with the Aleutians to the north, Antarctica to the south, and so on, allows the building concept to be clearly understood by its visitors. Blue exterior walls and red glass roof forms, crowned by glass skylights, further express the Ring of Fire.