noun
mountain ridge; near a mountain
Refers to the area along the base or edge of a mountain, or the ridge itself. Often used in descriptions of scenery or location.
山際に小さな集落がある。
There is a small settlement at the foot of the mountain.
夕日が山際に沈んでいく。
The sun sets behind the mountain ridge.
山裾 specifically means the foot or base of a mountain, while 山際 can also refer to the ridge or the area near the mountain.
Compound of 山 (yama, 'mountain') and 際 (giwa, 'edge, side'). The reading やまぎわ is a straightforward combination.