This past weekend we went to Osaka with M's parental units, and since they boast one of the world's largest, the aquarium was on the list to visit. The set-up was interesting, the aquarium is based on the Ring of Fire and Ring of Life areas in the Pacific Ocean, and after riding an enormous escalator up to the 8th floor, visitors wind their way back down looking at the marine life from different areas.
What I spent a lot of time looking at was the back of people's heads. The place was packed. Many viewing windows were stacked 5 or 6 rows deep. Not the ideal situation for taking in exotic sea life.
The jellyfish area though was somewhat empty (comparatively anyway), which I found surprising because there were so many lovely ones. I was completely enthralled.