|Sources: The Burning Crusade|
An'daroth is a ley-line nexus once used by the high elves of Quel'Thalas prior to the Scourge invasion located in the northwestern Ghostlands. It's found east of Goldenmist Village and west of Elrendar Crossing. Around the time the blood elves first joined the Horde, a night elven camp of Sentinel spies and their leader made this area their base of operations.
An'daroth, along with An'telas and An'owyn, was a heavily-guarded, hidden locations in Quel'Thalas which held a piece of mooncrystal for the Key of the Three Moons, that, when combined, produced a powerful key to bring down the second Moongate. During Arthas's mission to the Sunwell, to resurrect the rotting remains of Kel'Thuzad, a traitorous Quel'Thalas wizard named Dar'Khan Drathir provided Arthas with information about the Key of the Three Moons and their whereabouts.
Soon after, Lor'themar Theron and his elven rangers arrived to the camp, only to be attacked by reanimated elves. Here, Theron lost his left eye and only the timely arrival of Halduron Brightwing and his group saved the future Regent Lord.