'After me, I think,' said Dumbledore, and he walked through the archway with Harry on his heels, lighting his own wand hastily as he went. An eerie sight met their eyes: they were standing on the edge of a great black lake, so vast that Harry could not make out the distant banks, in a cavern so high that the ceiling, too, was out of sight. A misty greenish light shone far away in what looked like the middle of the lake; it was reflected in the completely still water below.
