But when Sir Tristram had come somewhat nearer, he perceived the windows of the castle shining against the sky, and he saw the gateway thereof, and the roofs and the chimneys thereof, so that he knew that it was a castle of great size and strength and no wall of rock as he had at first supposed it to be; and he wist that this must be the castle of that wicked and malignant knight, Sir Nabon, whom he sought.