One hour open top bus tour of all the city and bay area well worth the money and time. Pick up right outside the castle, which is bang in the middle of Cardiff.
Thanks for your replies vehelpfulguy and Paul. I have had a look at those links, and I will def go on the bus tour - always good to help with getting your bearings.
Which weekend are you going away? There are lots of theatres and things to go visit in Cardiff, but these are date specific. To give you an idea, here are a list of theatre and clubbing events in Cardiff in June - http://www.viewcardiff.co.uk/listings.aspx
This site also deals with places to go out drinking and eating, you might find what you're looking for here.
Thanks Matt - your post was exactly what I was after a few weeks ago but it is a bit too late now. You maybe didn't notice in my questiuon that I said I was going on the weekend of the date that I posted?!
I had a great time anyhow. Lovely place and very friendly people. I suspect I will go back again sometime and I will be able to use the link you have sent me.
Thanks again for taking the time to send me the info.