Longman Dictionary of Contemporary English
rock face
noun
EXAMPLES FROM CORPUS
▪ Below the bushes lay a ledge and then a sheer rock face plunging forty feet to the clay-reddened lake.
▪ Steve had to fix a belay around a boulder while the porters lowered barrels, bags and sacks down the rock face.
▪ The body in its shroud of ice stayed fixed to the rock face.
▪ The heat-seekers would be drawn by the steaming wound in the rock face, Defries realized; they'd ignore Daak.
▪ The path down to the beach was a precarious one, tiny steps hewn out of the sheer rock face.
▪ We stopped to look at the ruins built into a cut in the rock face of one of the cliffs.
Wiktionary
rock face
n. An exposed, roughly vertical expanse of rock