Barad-dûr: The Tower Built on Sauron's Soul | Tolkien Lore Explained

Barad-dur, the Dark Tower of Mordor, stands as the supreme expression of Sauron's will to dominate Middle-earth. Built across six hundred years by a corrupted Maia of Aule whose love of order curdled into tyranny, the fortress was bound to the One Ring at a metaphysical level, its foundations infused with Sauron's own externalized power. Tolkien deliberately never describes the tower's interior, making it a literary embodiment of evil as absence: eyeless prisons, immeasurable pits, gaping gates. The Last Alliance besieged it for seven years, losing Gil-galad, Elendil, and Anarion before leveling its walls -- yet the foundations endured because Isildur kept the Ring. Three thousand years later the tower rose again, crowned by the Window of the Lidless Eye, projecting terror across Middle-earth. When the Ring entered the fires of Mount Doom, everything it sustained collapsed in a single breath, proving that craft built to dominate carries its own destruction within it.