Thanks so much for having provided this information last month. I final remembered to go back and try the link for 3D cities the other day (http://www.3dcities.com.pt/) and it was working. It's not quite what I was thinking of, but very interesting none the less.

They currently have a demonstration available on their Web site which is called "3D Lisboa-Dakar". I downloaded the software and had a look and it gives a virtual "fly over" of Lisbon which was quite helpful.

Thanks again. Susan in Peterborough