Wiktionary
open valley
n. (context roofing English) a method of valley construction in which the steep-slope roofing on both sides are trimmed along each side of the valley, exposing the metal valley flashing.
Usage examples of "open valley".
She looked down the other side into a deep, lush riddle of canyons and washes that merged into an open valley.
Hakeswill ran into the open valley, his breath harsh in his ears, his feet numbed by the snow, and he glanced left and saw he had far outrun the Fusiliers, and he thought he saw Sharpe, but that was no concern for this moment, and then he saw the Riflemen beyond Sharpe and he feared their weapons so he cut right, sprinting in desperation, the gold in his greatcoat pocket, the musket heavy in his hand.