Mordor
The land of Mordor was bordered by mountains
on three sides, with an open plain in between. Sauron settled in Mordor
in the Second Age, around the year 1000. In the northwest corner Sauron
built the Black Gate and the fortress Barad-dûr, and forged the One
Ring in Mount Doom. From Mordor he attacked the Elves of Eregion, but was
driven back by the men of Númenor. A thousand years later he was
captured by the Númenoreans. Following the destruction of their
island, he returned to Mordor in spirit form. He continued warring
against Men and Elves, until finally the Last Alliance of Elves and Men
marched upon Mordor and defeated him.
Gondor established several fortresses designed to keep the evil creatures from entering or leaving Mordor again, but their efforts dropped off after the plague, and the evil forces gathered. The Nazgul went to Mordor and prepared it again for Sauron’s return. During the War of the Ring, Sauron’s forces gathered in Mordor. The Host of the West marched upon Mordor to distract them from Frodo’s quest to destroy the One Ring, and when the Ring was destroyed in the fires of Mount Doom, Sauron was defeated and Mordor was devastated by earthquakes.