Osaka is Japan's third biggest city and according to my guide book has a GDP output similar to Canada. Osaka also has Japan's best aquarium and a Universal Studios among its attractions but otherwise there wasn't a huge amount to sightsee.
I started my day here by going to Osaka castle, Osaka's main attraction in the city is Osaka castle, which is famous in Japan for having two elevators, one on the outside of the tower and one on the inside. The castle and tower were quite impressive and the displays in the tower had a timeline of the life of Toyotomi Hideyoshi who is describes as Japan's second great unifier. He lived in the Sengoku period in Japan and had a very interesting life. His legacy shaped Japan, by crucifying Christians, invading Korea and only allowing the Samurai class to bear arms.
After the castle I walked to downtown Osaka and the main train station. The shopping malls there were huge even by Japan's standards. The city has a lot of haphazard urban development but it was interesting in its own right.
On the other side of the station was Umeda sky building, one of the most interesting buildings I had ever seen with two towers linked by a ring at the top. There was a 'sky garden' viewing platform at the top which had stunning views over all of Osaka and I managed to catch it at sunset, seeing Osaka in the day and the night.
Next stop on my way down Japan is Hiroshima, the site of the first ever atomic bomb victim.