The "story" of Tetsuko no Tabi is that a manga artist is asked by her boss to accompany him and a travel-writer on various train trips around Japan and draw a manga about it. The kicker though, is that it's completely non-fiction - the creator really did go on all these trips, and the manga simply records what happened, with no embellishment. The anime is based on a seinen manga by Kikuchi Naoe and Yokomi Hirohiko, serialised in IKKI.