The Three Step Pass is the pass between the Mountains of Rain and Night, which Morgarath uses to let his Wargals attack Araluen via the Plains of Uthal in The Burning Bridge.
Description[]
It is a dark, damp and forbidding place, sheer cliffs twisting along for at least five kilometres, acting as boundary between Araluen and the Mountains of Rain and Night. During Morgarath's exile, Araluen kept a small force near the mouth of the gorge. They expected Morgarath to attack from the pass, as it was the only place he could use to attack in numbers.