When arriving in Paris on CDG aiport which RER should I take to my hotel near the Eiffel Tower
Take the RER B train from CDG (either T1/T3 or T2 station, it's the same train) until Saint Michel Notre Dame station. Then transfer to RER C train (use the same ticket) in direction of Pointoise or Versailles Rive Gauche or Saint-Quentin-en-Yvelines. Any of these three destinations should work. On the train platform (at Saint Michel Notre Dame) check the stations panels to see which stops will be served. You'll want to get off at Champ de Mars Tour Eiffel station stop.