"Improvise," the Doctor responded with a grin. "Just like right now. All right?" He made a show of looking her over, even though he was certain she was just fine after the impromptu skate across the ice.
"Now then. We ought to decide on a way to mark our path so we can find the way back out again when we're finished. I hate to damage the natural setting, but I suppose I could sonic the stone in a way that we can track without it being obvious to anyone who happens across this place in a day or two."