Cirith Ungol was a pass through the Ephel Dúath that led into Mordor.
Drawing
J.R.R. Tolkien made a drawing that shows the top of the stairs of Cirith Ungol, the entrance to the tunnel with the pass of Cirith Ungol after the exit from the tunnel and the topmost turret of the Tower of Cirith Ungol behind a mountain peak with another broader pass on the right side of the pass of Cirith Ungol and a mountain ridge between the pass of Cirith Ungol and the other broader pass.
Description
The pass was located in a cleft on the slope of the mountain on the north-east side of the Morgul Vale, above and to the north of the Morgul Pass. It could be reached by taking a narrow path that began at a gap in the stone-wall on the left side of the Morgul-road near the bridge over the river Morgulduin, which wound up the mountain on the northern side near the entrance of the Morgul Vale, climbing the Stairs of Cirith Ungol, passing through a tunnel, and taking a long flight of broad, shallow steps to the cleft with the crown of the pass after which the path turned left and plunged steeply down to the Tower of Cirith Ungol. From a gate in the south-eastern side of the wall that enclosed the courtyard of the tower a broad road ran on the edge of a precipice and then turned southward and wound down to join the Morgul-road. Despite the danger posed by Shelob, it was the swiftest path from Minas Morgul over the mountains.
The pass of Cirith Ungol was probably named after the giant spider Shelob, who dwelt there. It was also referred to as the "high pass".
Before the War of the Ring
The pass was first called Cirith Dúath ("Shadow Cleft"). This name was used during the War of the Last Alliance, when Isildur sent his sons Aratan and Ciryon to Minas Ithil to prevent the forces of Sauron from escaping through the pass. After the War of the Last Alliance, the Men of Gondor built a tower at the eastern end of Cirith Dúath as an eastern outpost of the defences of Ithilien to keep enemies in Mordor. This tower was later called the Tower of Cirith Ungol.
War of the Ring
During the War of the Ring, in March T.A. 3019, Gollum led Frodo Baggins and Samwise Gamgee up the Stairs of Cirith Ungol, into Shelob's lair.
Artwork
Cirith Ungol
Donato Giancola