Here’s the Wiki article on “The Long Walk”, which turned out to be fiction.
http://en.wikipedia.org/wiki/S%C5%82awomir_Rawicz
Notfiction. Some aspects are questioned. And of course it is Wiki
The Long Walk by Slawomir Rawicz (New York: Harper, 1956) was reprinted several times and even digitized. However, as I read it, I began to question the narrative. The writer told of surviving more than a week in the Gobi Desert in the summer without so much as taking a drink of water, and of meeting "abominable snowmen" in the Himalayas. By the time I finished, I was convinced that this was a work of fiction.