The French state railway company SNCF has a lot of nice maps of their rail network, some of which I’ve posted here before; of particular interest, though, is the Atlas du réseau ferré en France, which gathers them into an 86-page booklet, and includes a lot of diagrams showing, for example, passenger and freight volumes. It’s available here as a flipbook and can be downloaded as a PDF if you give them your email; I’d be over the moon if it existed as a hard copy.