One of the seven Beacons of Gondor, the fourth that would be lit when Minas Tirith called for aid from Rohan. Its attendants would set fire to their Beacon when they saw a flame on Nardol, far to the east, and their own Beacon-fire would be answered by that on the peak of Min-rimmon to the west. All these Beacon hills lay among the White Mountains as they came down into the plains of Anórien, the fief of Gondor that lay on Rohan's borders.
Notes
1
The dating of Erelas' beacon is far from clear, but we do know that it was not one of the original three beacon-hills of Gondor that predated the coming of the Rohirrim. The beacon would almost certainly have been placed after the creation of Rohan in III 2510, but no specific date is recorded.
2
At first sight, Erelas appears to be a Sindarin name, and indeed might be taken to contain the name elements er- 'one, single' and -las 'leaf'. However, Tolkien specifically notes that this was a Pre-Númenórean name of forgotten meaning. He goes on to explain that, being a treeless hill, the apparent Sindarin origins involving the word for 'leaf' cannot realistically have been applicable.