It was presented as a true account of a trip around America by John Steinbeck, accompanied by his poodle. It was a best-seller, and has moved into that vague status of modern classic.
But it turns out it wasn't a true account. Bill Steigerwald, a journalist, has a written rather revealing article at Reason:
Using clues from the book, biographies of Steinbeck, letters Steinbeck wrote from the road, newspaper articles, and the first draft of the Charley manuscript, I built a time-and-place line for Steinbeck’s trip from September 23, 1960, to December 5, 1960. The more I learned about Steinbeck’s actual journey, the less it resembled the one he described.What Steinbeck did was turn a boring trip into an interesting and inspiring one. He turned it into a novel. But he claimed it as true.
Perhaps he figured
he'd gather more boodle
by claiming as true
his tale of the poodle.