Hi, I am wanting to get from CDG to Gare du Lyon on the train, do I need to book these tickets in advance? What is the cost and travel time?
No need to book tickets for RER train from CDG to Paris Gare de Lyon.
You would take the RER B from CDG to Chatelet les Halles, then take RER A (direction Marne La Vallée-Chessy or Boissy St Léger). Another option includes changing from RER B to RER D at Gare du Nord, direction Melun or Malesherbes or Corbeil Essones