This is a double decked train of SNCF Transilian to Pontoise, Île-de-France. This area is a part of greater suburb of Paris in my understanding.
It is notable and convenient to me that they allow passengers to carry bicycle in the train. Thanks to this, I can travel around various places around there by train and my bicycle.
Meanwhile, double-decked commuter trains are difficult in Japan except green cars included uniformly in metropolitan Tokyo by JR East and some other examples. Double-decked local or commuter trains are widely seen in France and other countries.
Pontoise is also famous for the history of Impressionist artists. It seems that Gare Saint-Lazare (in Paris) and the railways from that terminal along Seine River is a place to grow such good cultural environment.