A few miles from here
a frost-stiffened wood waits and keeps watch
above a mere; the overhanging bank
is a maze of tree-roots mirrored in its surface.
At night there, something uncanny happens:
the water burns. And the mere bottom
has never been sounded by the sons of men.
On its bank, the heather-stepper halts:
the hart in flight from pursuing hounds
will turn to face them with firm-set horns
and die in the wood rather than dive
beneath its surface. That is no good place.
– Beowulf, Seamus Heaney (trans.)
Lines 1363-1372: Hrothgar’s description of the bone-chilling, haunted mere that Grendel’s mother calls home.