DescriptionAt the top of the pass was a cleft with two rock horns on each side, with the tower on the northernmost. The tower was built of black stone against the eastern rock face. There were three tiers, each set back from the last. The two sides face northeast and southeast, and meet to form a bastion pointing eastward. At the top of the tower was a tall round turret overlooking the pass. A high, outer wall surrounded the bottom tier, and formed an overhanging parapet to prevent enemies from climbing over.
A road ran from the pass of Cirith Ungol to the tower, with the fortress to the north and a sheer precipice to the south. In the southeastern side of the outer wall of is the main gate, guarded by two hideous statues on each side, called Watchers. Each statue was of three bodies connected to one vulture-like head. Also on the southeastern wall of the lowest tier of the tower was the gateway leading inside. A hallway with rooms branching off traveled back through the building to a curved archway called the Undergate, which led to Shelob's Lair. To the right of the Undergate was a spiral staircase leading up through the tower, opening up onto the roof of the third tier. On the western side of the roof was the round turret. A winding staircase went up to a passageway running across the turret. Above the passage was a trapdoor leading to a room in the very top of the tower.
The fortress was associated with the mountain fortress of Durthang in Northwestern Mordor, and the Towers of the Teeth at the Morannon. All were part of the Gondor defensive scheme that proved too costly to maintain in the course of the hardships of the next sixteen centuries.
The Tower was built by the Men of Gondor after the War of the Last Alliance to guard the province of Ithilien from the evil forces inside Mordor. The principal purpose of the sturdy tower of Gondor was to defend Ithilien from attacks from Sauron's remaining servants. For this reason its two bastions were directed to the north and south-east. It also served to stop Sauron's servants from returning to Mordor through the pass. Gondor held the tower until the Wainriders attacked Gondor and killed Narmacil II, causing Gondor to recall its troops, thus allowing evil creatures to once again enter Mordor.
The tower itself slowly became a stronghold of the enemy and was commanded by Uruk-hai and Orcs. During Sauron's second return it was used by Orcs to watch the lands of Mordor to prevent the desertion of any of Sauron's forces. During the War of the Ring, Frodo was imprisoned here after being captured by Shagrat's orc party as he lay on the ground paralyzed by the poison of Shelob. They intended to hold him for questioning but when he was searched, Frodo's Mithril-shirt was found. Afterwards, orcs from Minas Morgul led by Gorbag did battle with Shagrat's orcs to possess it. By the time the battle was over, orcs and Uruk-hai from both sides had nearly wiped each other out, allowing Sam to enter the tower unopposed and rescue Frodo.