There's something very special about walking into a train station in the heart of a European city, and seeing a departure board that looks like this: http://www.enjoy-europe.com/hte/chap17/images/P1020015-Bruss...; the sense that you could just buy a ticket and jump on a train to anywhere. You tend not to get the same feeling from an airport departure board, where for the most part you couldn't just buy a ticket and fly to any of those destinations.