1.About it
Mordor was protected from three sides by large mountain ranges, arranged roughly in a rectangular manner: Ash Mountains in the north, Ephel Dúath in the west and south. In the northwest corner of Mordor the deep valley of Udûn was the only entrance for large armies, and that is where Sauron built Black Gate of Mordor. In front of the Black Gate lay the Dagorlad or the Battle Plain. Sauron's main fortress of Barad-dûr was at the foothills of Ered Lithui. To the southwest of Barad-dûr lay the arid plateau of Gorgoroth and Mount Doom; to the east lay the plain of Lithlad. Mordor's geography was excellent for defense against enemies attacking on all fronts, for nearly unscalable mountains defended Mordor on three sides, while the broken, jagged land of Gorgoroth and Nurn would greatly impede any army that managed to break through.

Mordor's dry and blasted geography would also be extremely unfriendly to any army bivouacked on the plains, forcing a withdrawal within days (unless they have stores sufficient for months). The only other path for armies to cross into Mordor from the west, over the Ephel Duath was the Pass of Cirith Ungol. Isildur originally built the city of Minas Ithil to guard this pass from evil things attempting to re-enter Mordor, but in the Third Age the population of the city waned and was conquered by the Nazgûl. It became the home of the Ringwraiths and was renamed Minas Morgul- the Tower of Sorcery, and was thereafter a great stronghold of evil, ever at war with Gondor to the west, until the end of the War of the Ring. To escape the vigilance of Morgul, to enter Mordor one would still have to get past the lair of Shelob, and the Tower of Cirith Ungol- a feat only Frodo Baggins and Samwise Gamgee (led by Gollum) ever accomplished- though not without being waylaid by the great fearsome spider Shelob, and Frodo being taken prisoner to the Tower of Cirith Ungol.

The southern part of Mordor called Núrn was slightly more fertile, and moist enough to carry the inland Sea of Núrnen. Nurn was made somewhat fertile because the ash blown from Mount Doom left its soil nutrient rich, thus allowing dry-land farming.

To the west of Mordor was the narrow land of Ithilien with the city of Osgiliath and the great river Anduin, while directly East of it was Rhûn, and to the southeast, Khand.
Mordor's DuoSpire

Mount Doom and the Dark Tower

The east of Mordor is by far the least mentioned of any of Mordor's geographic notes and descriptions. One might assume that the easiest route to Mount Doom would be for the Fellowship to journey through the 'unguarded' section of the east, where no mountains guard; however, we are told in the Fellowship of the Ring that the area was heavily defended by a line of border forts facing Sauron's allies in Rhûn. In theory, these forts have no use, because to get there they would have to pass along the western edge of Rhûn, and Sauron's strongest allies, the Easterlings, abode there. Also it would have been difficult to pass unnoticed because of the many roads running from Mordor into Rhûn were always being marched along by Easterlings entering Mordor or patrolling the roads and borders.


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