When we arrive in CDG from the US, we would like to immediately get on TGV to Strasbourg, but stop in Nancy along the way. I am confused about where to catch the TGV to Strasbourg. The map that I saw didn't show any trains to Strasbourg, then I noticed there are 3 CDG stations. So I have several questions. Can we walk to the correct TGV station to go to Strasbourg from CDG? Is there a stop in Nancy that we could just get off or do we have to buy 2 separate tickets?
There is only one TGV station at Charles de Gaulle. The other two you're seeing are stations on the RER suburban rail system for trains into Paris. You can check schedules and buy tickets at www.tgv-europe.com. Claim to be in Canada or the UK to avoid being bumped to the US Rail Europe site which often has fewer trains available and higher fares. There are only a couple of direct trains a day from CDG to Strasbourg and I don't know if any of them stop at Nancy. Also check for trains to Nancy from Paris - you can get the RER train from CDG to the Gare du Nord station in central Paris, which is a short walk from Gare de l'Est which is the starting point for trains to Nancy and Strasbourg. You will need to book a separate ticket from Nancy to Strasbourg, which you can also do at www.tgv-europe.com. French rail tickets go on sale around 90 days before travelling. Booking at this time allows you to get very cheap "Prems" tickets, but these are strictly limited to a single train. If your flight gets delayed and you miss the train you will have to buy a new ticket at full price. Are you intending to just tour Nancy briefly or stay for longer? I would say that there is enough in Nancy for a couple of days, especially if you like early 20th-century art/architecture. If you are staying, I highly recommend the Hotel de Guise, which is a quiet hotel in an old building in the medieval city area. Its only disadvantage is that there is no elevator.
Trains to Strasbourg do not go through Nancy; they are very fast TGV trains which only make a couple of stops, and Nancy isn't one. They don't call at Charles de Gaulle Roissy either. You need to take the RER into Gare du Nord and walk to Gare de l'Est. Gare is French for station, Nord is north, l'Est is East. The TGV to Strasbourg and TGVs for Nancy start at Gare de l'Est. There are direct TGVs to Nancy from Gare de l'Est. They are as fast as 90 minutes non stop. Regional trains connect Nancy with Strasbourg and take about 90 minutes. The same ticket you use to get on the train in Paris allows you to get off at your destination. It will be specific to the exact TGV you take because it includes a reserved seat. You aren't doing this on a pass of some sort are you? You will need a different ticket for the regional train to Strasbourg.
Sorry Nigel, but the Lille-Strasbourg trains stop at CDG. I checked on the UK site for journeys from CDG to Strasbourg on Tuesday and got four departures with no changes listed. There aren't any direct trains from CDG to Nancy though.