Eilenach
From Tolkien Gateway
Eilenach was the second of the seven beacon-hills of Gondor, after Amon Dîn in the east, and it was the highest point of the Drúadan Forest. It had a sharp summit, uncapable of sustaining a large fire. Its main purpose was to relay the fire of Amon Dîn to Nardol.
Etymology
On the origin of the name, Tolkien wrote Eilenach is "probably an alien name, not Sindarin, not Númenórean, or Common speech." Perhaps it was pre-Númenórean.