21.   It found its way over the balconies of the Sheraton Hotel rooms that cling to the rock face, and probably awakened a few guests trying to sleep in.

22.   It could be done, as Gleeson demonstrated, by bracing your back against the rock face and your feet against the overhang and shimmying up the rock.

23.   It says a lot that the chance to gaze up at their chiseled rock faces on Mount Rushmore makes anything else superfluous.

24.   It is, instead, where the climb ends at the anchor in the middle of the rock face.

25.   It climbed a wet and slippery rock face.

26.   It tumbles over a sheer rock face, crashes into a bed of broken stones below and courses past dense thickets of rhododendron and towering hemlock trees.

27.   Mission engineers posted an image on the World Wide Web of the rover with its left rear wheel up on the rock face.

28.   Often enough, they go straight through rock, creating accidental geologic field laboratories, the exposed rock faces called road cuts.

29.   One arch is formed against a sheer rock face.

30.   One walks down the narrow path between sheer red rock faces.