Spike,
I was there last year when we travelled to Greece. It is a very nice, very old city, with a beautiful wall that surrounds it. Take in the sights if you want, or just walk along the wall, for a price of course. I went to the Island of Lokrum, a beautiful forest preserve just off the mainland of Debrovnik. The Island use to be a housing location for orphin children and nuns. In Debrovik, I went to the local market and bought some very large cherries, and took them back to the ship. Even though it is Croatia, many of the stores still accept the Euro, so do not worry about that. Well, enjoy your trip.
Mark