The Scarlet Watchtower is a ruined scout tower located in southern Tirisfal Glades near the entrance to the Sewers of the Undercity. It is under the control of the Scarlet Crusade, who use it to keep a watchful eye on flight routes coming to and from the Forsaken capital. It is one of four Crusader's Outpost towers in the Tirisfal Glades.
This particular tower is commanded by Captain Perrine, who guards a chest that contains [Egalin's Grimoire].