The Hidden Treasure of Glaston, by Eleanore M. Jewett

The story begins on a dark and stormy night.  In the midst of a storm, the residents of the monastery in Glaston are awakened in the middle of the night.  A nobleman, clearly fleeing something, asks to leave his son in their care.  In exchange, he offers several rare and valuable books which will be treasured by the residents.  Rather than staying to rest, he then ventures back into the storm to continue his journey.

The young man, Hugh, is lame in one leg and knows that a future as a knight or nobleman is probably not feasible.  So he resigns himself to an apprenticeship, although he soon grows fond of the men who he works with.  During a walk outdoors on his own, he also encounters another young man his age: Dickon, an oblate, whose tasks keep him elsewhere in the monastery.  The two become fast friends.  Dickon would like for them to become sworn brothers, but Hugh refuses to disclose his origins.

When Hugh suddenly encounters a man from his past fleeing an angry crowd, he steals a horse and cart to speed the man to the sanctuary of the church.  The man, Jacques, was a member of the staff in Hugh's household, and it is revealed at that time that Hugh is the son of Hugh de Morville, who was fleeing the country due to his role in the murder of the Archbishop Thomas Beckett.  Hugh can then be reconciled to Dickon- he had only maintained secrecy because he had sworn an oath to his father to do so for his own protection.  With no secrets between them, Dickon takes Hugh to his secret hideaway- a cavern underground which may have once allowed the monastery's residents to flee from Vikings.  There appears to be no entrance besides an opening in the rocks too small for a grown man to enter.  And some treasures still remain there- a sword, a jeweled altar, and a number of loose pages written in ancient Latin.

When Hugh, working with the monks to clean old, useless parchments for reuse, discovers similar writing hidden underneath the surface, he realizes that they (and the secret pages from the cavern) relate stories of the Holy Grail.  He knows that Joseph of Aramithea had carried the Grail to this region and established the church here.  With Dickon's help he resolves to translate the pages secretly so that they can solve the mystery of the location of the missing Grail themselves and present it to the church.

It's evening and I'm tired and I'm somehow feeling as if I've never written a more dry description of a novel.  But I really, really, loved this one.  It had mystery, folklore, and a bit of adventure to it.  And it's written in such a way that it's timeless- it's a book that a child today could enjoy just as easily as one sixty years ago when it was first published.