The Gare de Lyon is served by two metro lines (1 and 14) and two RER lines (A and D). Without taking into account the time it will take to buy transport tickets and without counting the vagaries of metro and RER traffic, it will take you on average 25 to 30 minutes to reach La Défense. At rush hour, lines 1 and RER A are crowded, do not expect a serene journey time and prepare to be hot!
If you are in transit and have to reach another station , plan to face the long corridors of Châtelet-Les Halles for the Gare de L'Est and Gare du Nord. Subways and RER remain an economical solution, certainly, but not recommended when you have a timed time and you need peace of mind.
10 bus lines serve the capital and the inner suburbs, an economical and ideal solution for enjoying beautiful views during your journey, provided that you are not in rush hour on a crowded bus. Despite reserved corridors, it is a solution to keep if you have time in front of you due to frequent stops.