Osaka is a city with many architecturally interesting buildings and amongst them the Aquarium Kaiyukan certainly stands out. Inaugurated in 1990, Aquarium Kaiyukan was designed by Peter Chermayeff LLC, an American company specialized in aquarium architecture. The best angle to admire its shape is from... above and the nearby Tempozan Ferris Wheel offers the best opportunity for this (as you can see from this photo).
Travel tip: If you like to visit it (and I warmly recommend it), you can buy the Osaka KAIYU Ticket (2400 yen) a pass valid for one day, which offers entrance to the museum (which by itself costs 2000 yen) and unlimited rides on subway lines, new tram lines and city buses in Osaka city. Plus 50% discount to 30 other attractions, like the Tempozan Ferris Wheel mentioned above (which costs 700 yen) or the Osaka Bay Cruise Santa Maria (which is 1500 yen).
EXIF info:
Nikon D700
Lens: 24-70mm F/2.8G
Focal Length: 70mm
Aperture: F/7.1
Shutter Speed: 1/400s
ISO Sensitivity: ISO 200