noun
gorge
GORJ/ɡɔːrdʒ/
A deep, narrow valley with steep rocky sides.
A river rushes through the gorge between steep rock walls.

Etymology
The ancestor gurges meant “gullet” or “throat.” The throat image extended to a narrow passage and then to a deep, narrow valley, a landscape sense already present in Old French.
In context
meanwhile Roy and Langley arrive at the gorge as they rein in Langley points out the gorge below them which is like a long valley with steep sides