The fourth book in the Prydain series by Lloyd Alexander, Taran Wanderer, 1967, follow the adventures of Taran, the former assistant pig-keeper. It is the Pilgrim's Progress of YA fantasy, except without the pilgrims.
The tale itself is an ambling one, wandering just as much as the protagonist. Taran bumps his way through an episodic narrative, growing up along the way. Along the way, he meets many peoples, tries many jobs, and earnestly goes about his quest to discover his parentage.
While well written, the book feels empty at the end. It is as if his journey only required that it fill 50,000 words, and then should be done. Exactly how those 50k words happened didn't seem to matter much.
You can cal me a bit thick-headed for missing all the symbolism and allegory. I do that. Each episode does have it's After School Special lesson to teach, with some of them clearer than others. The fault of the story is not that is has allegory, but that you care so little about the allegory that you just don't bother thinking about it.