Arthur: King of the Middle March by Kevin Crossley-Holland

Kevin Crossley-Holland has long been fascinated by the Arthurian legends. A decade ago, he wrote a set of radio plays around the character of Sir Thomas Malory, the 15th-century author of the Morte Darthur, the greatest of all retellings in English of the knights of the Round Table. And for the last six years or more he has been writing the trilogy of which Arthur: King of the Middle March is the final part.

If you have read the first two books, you will already know what's happening. The story in the foreground is set around 1200, in a medieval world so real that you can smell, touch and see it. Its hero is Arthur de Gortanore, a young squire who lives in the Welsh borders and is fired with passionate idealism to become a knight and join a crusade to Jerusalem.

First he has to learn a good many lessons. Some are practical (how to handle a sword and ride a destrier, how to manage his lord's manorial tenants). Some are moral (what is true justice? How do you know if you really love somebody? Can Saracens be better men than Christians?).

Arthur gets insight not only from his experiences, relatives and companions, but from the visions he sees in a magical stone which works as a window into the world of the legendary King Arthur. He was given the stone by Merlin, who is both alive in the Middle March and trapped by Nimue's spell in the legendary world of Camelot. Some of the stories (Lancelot's love for Guinevere, Mordred's betrayal of Arthur) are familiar; others are little-known.

The third book may at first disappoint readers expecting the sort of climax that Rosemary Sutcliff or Geoffrey Trease used to conjure up in their crusading yarns. Arthur and his companions find themselves in a mire of political corruption when they arrive in Venice in search of a ship. Jerusalem, the promised land, is all but unattainable, and Arthur has to choose between duty and glory.

Yet I suspect that the delicately downbeat conclusion of Arthur of Gortanore's adventures will be remembered for longer. This is not a book to hurry, but to read a little every night and reflect on. Like the original Arthurian stories, it is essentially a morality tale, about growing up and learning to see the world without innocence, but also without cynicism. Brutality and self-seeking are universal evils, but can be countered by bravery and loyalty, love and forgiveness.

Like the first two books, this one is is beautifully arranged. There are exquisite maps of the Middle March and the route to Italy. The illustrations are close kin to the charming woodcuts printed in Wynkin de Worde's Morte Darthur in the 1490s. Many chapters are so short that they work like fast cuts in a film.

Crossley-Holland is, of course, a poet, and the simplicity, musicality and laconic directness of his writing reflects this. Most enduring of all are the characters: Arthur, honest and puzzled, the ominously Guinevere-like Lady Winifred and, most of all, the irrepressibly honest and gutsy Gatty.

The reviewer's life of Thomas Malory will appear next year