“Outside, Great! Inside, not so much...”
Osaka castle looks absolutely amazing from the outside!
The grounds of the castle are huge! you can explore for a very long time and find many cool things to see. The stone walls are super big and the drop to the rivers below is super cool. It's a very beautiful place. The castle itself looks in pristine condition, which leads into my next point.
The inside was very, very boring. For me at-least.
It's very new inside, they even have a very large elevator in the middle. Inside is a very swanky museum full of old samurai history, and old artifacts from the period the castle was used. But it just wasn't that interesting. I would recommend other museums over the inside of Osaka castle any day.
The view from the top of the Castle is quite nice, though doesn't constitute paying the entrance fee, in my opinion.
All in all. Its okay, you might as well check it out.