WE ARE ON THE LOOK-OUT for doing things greener and one of our thoughts will take us on a journey involving three trains from London, certainly within the next 20 months. Once in London, we check in at St Pancras at 1800 for a Eurostar to Brussels, where we then catch the City Night Line, an overnight express to Berlin. We probably will book a sleeper, like in the photo with Ruth at left, not a couchette. There's a light breakfast offered in the bistro car, guaranteeing we'll arrive refreshed in Berlin's Hauptbahnhof around 0800. Then it's across the terminal to an air-conditioned EuroCity train that will snake us through Dresden, then the Elbe Valley and into the Czech Republic. We get to Prague at 1330 and walk to our hotel. We can make all the train connections and return to London for less than €500 each.