Thanks for your insights and guidance. We are now committed to spending 4 days in Paris, 2 days in Caen, then travelling by train to Frankfurt and nearby Hanau where I was stationed in the Army 1972-75. Depending on airfare combinations, we will return to JFK either via Frankfurt oo take the train back to Paris for out flight home.

Does anyone have an idea of the cost of train travel between Paris & Frankfurt or special/hidden deals that may not show up on the SNCF website?