This is the RER (Réseau Express Régional) stop at Charles de Gaulle-Etoile - probably the stop I use most as it brings me into Paris from my home in the suburbs and is a major interchange linking up with various metro lines. As I was standing waiting for my train the other day, I was struck by the layers in front of me - the autism awareness advertisements above my head, the tourist advertisements on the quay opposite, and the people waiting to travel in the opposite direction from me.
Interesting shot, and yes, the people look tiny, so they must be massive posters. I did not attempt to use any of the metro or RER in Paris....thought I'd leave that for the experts! lol