osaka citytrip few hours

We have a stop in Osaka and would like to go to the castle and other sites. Tips as to how to do this?

Marijke (Holland)

This page explains transportation in Osaka (in the lower half of the page):
http://www.japan-guide.com/e/e4006.html

Tips depend on where you arrive from and depart for (KIX Airport, Shin-Osaka Shinkansen station, etc.)....

We arrive 23 sept. at Kansai Intl. 08:05 and are leaving: 15:30 to New-Zeeland. I do not know what time we have to be back on the airport. So we have only a few hours.

You won't have sufficient time to make a round tour to Osaka city centre. I recommend
http://www.kansai-airport.or.jp/en/transittour/index.html

or

http://www.jnto.go.jp/eng/arrange/attractions/facilities/castles/83dn3...
if you definitely wanna see a Japanese castle.