Tower-gate

The Tower of Cirith Ungol was part of the defences raised by Gondor after the War of the Last Alliance, ringing Sauron's Dark Land of Mordor. These defences held for centuries, but gradually the watch of Gondor failed and the Gondorian fortresses fell into the clutches of the Enemy. The Tower of Cirith Ungol was captured by the Nazgûl some two thousand years after its building, and so it became a watchtower for Sauron on his western borders.

The Tower-gate was a wide arched gateway reached by a path that ran from the main road through the high pass of Cirith Ungol. The gateway led through the outer wall of the Tower to an inner courtyard, but it needed no physical gate to bar the way through the Tower's wall.¹ Instead the Two Watchers held the gateway, dread beings carved from stone but sentient. These Silent Watchers were capable of holding the entrance with a powerful barrier, or raising a shrieking alarm.

The guard of the Watchers was breached by Samwise Gamgee during the War of the Ring, who used the gleaming Star-glass of Galadriel to break their wills and allow him through the Tower-gate and into the Tower itself. Having rescued Frodo Baggins from within, he used the Phial once again to pass out of the gate. On this second use, the conflicting powers of the Star-glass and the Watchers were too great for the Tower-gate to withstand, and its arched gateway collapsed. Thus the Tower-gate of Cirith Ungol was destroyed, having stood on the borders of Mordor for some three thousand years.