And out of town and valley came a noise

As of a broad brook o’er a shingly bed

Brawling, or like a clamour of the rooks

At distance, ere they settle for the night....

the fortress is not merely an effective piece of decoration in the poem but part of its essential life, just as in the shoal

Of darting fish, that on a summer morn

Adown the crystal dykes at Camelot

Come slipping o’er their shadows on the sand....

and when Geraint rides

into the castle court,