From the book:
Before them, beyond the pillars, there was the slope of a low hill. And now a door opened in the hillside, and light appeared in the doorway, and a figure came out, and the door shut behind it. The figure carried a light, and this light was really all that they could see distinctly. It came slowly nearer and nearer till at last it stood right at the table opposite to them. Now they could see that it was a tall girl, dressed in a single long garment of clear blue which left her arms bare. She was bareheaded and her yellow hair hung down her back. And when they looked at her they thought they had never before known what beauty meant.
Thanks to Aslan’s Country for the scoop!