Cirith Ungol
The watchtower at Cirith Ungol (the "Spider's Pass") is an Orc stronghold that guards one of the entrances to Mordor.
Summary
The fortress was originally built by the Men of Gondor at the beginning of the Third Age, to guard the plain of Gorgoroth. It was maintained until TA 1640, when, weakened by conflicts elsewhere and by the Great Plague, Gondor withdrew its forces. Cirith Ungol sat unoccupied for at least 400 years. In TA 2002, however, the Nine Ringwraiths captured the city of Minas Morgul, assembling an army while Sauron controlled them from afar. It is likely that Cirith Ungol was also claimed by Orcs shortly thereafter.
Architecture
The fortress sits on a rocky ledge on the eastward slope of the Ephel Dúath. It is composed of three large angular tiers jutting out directly from the cliff, altogether about 60 meters tall and with many small windows. The tower is topped by a tall, round turret that rises above the mountain peaks.
The fortress is surrounded by a heavily fortified outer wall, about 9 meters tall. There is an arched gate in the southeastern side, out of which runs a broad road that leads to the Morgul Pass. This gate is flanked by the Watchers, two carved vulture-like figures inhabited by "some dreadful spirit of evil vigilance." Inside the gate is a narrow courtyard, paved with stones. Directly across from the gate is the door to the foot of the Tower. Inside the tower is a wide, straight passageway leading towards the mountainside, with many doors and openings on either side; the walls are dimly lit with torches. At the western end of this passage is a large arched door that leads to the "under-way," a tunnel that runs from the tower to Shelob's lair. To the right is a stairway leading to the upper levels of the tower. This staircase is dark, except for an occasional torch, and leads all the way to the third and highest tier. The staircase rises out of the center of the roof, and is covered with a small, domed chamber with doorways facing east and west. This topmost tier is roughly 18 meters across, with a low parapet.
The turret itself has four levels. A staircase climbs counterclockwise to the third level, making a complete circuit of the tower so that the landing at the second floor has a window that looks westward, and the third has an east-facing window. On each level is a hallway that cuts through the turret, with a room on the north and south side. The fourth and topmost level is reached by a trapdoor in the middle of the third-floor passageway. It has a high, narrow window facing west, and a red lamp hanging from its ceiling.
Cirith Ungol is made all of black stone, likely sourced from the Ephel Dúath. The stonework is of great quality, built in the Old Númenórean style. The battlements are supported by overhanging courses like inverted steps.