I assume that my readers are familiar with most of the landmarks shown on the overview map: Barad-dur, Cirith Ungol, Orodruin, etc. Additional sites not mentioned in LotR are drawn from ICE maps of the area; a description of each follows.
Barad-wath
One of the two fortresses that guard the vale between the tortured plateau of Gorgoroth and the more fertile fields of Nurn, Barad-wath was constructed by the kingdom of Gondor between T.A. 2 and T.A. 535 to guard against the return of evil things to Mordor. Not as stylized as some of Gondor's other barrier forts, this three-tiered fortress is a close copy of the tower of Cirith Ungol. Abandoned by Gondor in T.A. 1640 following the Great Plague, fell things rapidly occupied the tower. By T.A. 2000, Barad-wath was in use as a religious center for Variag and Nurniag tribal worship of Sauron's incarnations. As is common practice at strongholds of Sauron, human followers are housed within the structure's above-ground levels and Orc or Troll residents live in warrens below-ground.
Ostigurth
Built by Sauron in the mid-Second Age to control traffic between Gorgoroth and Nurn, this fortified city does not enter into the story by virtue of its complete collapse fifteen minutes into the adventure. It had a significant Orc and Troll population living in caverns beneath itself; those same caverns proved its undoing in the cataclysmic end of Sauron's realm.
Urlurtsu Nurn
South and slightly East of the southern edge of my map, Urlurtsu Nurn is a huge fortified city that dominates the slave-tended fields surrounding the Sea of Nurn. After the Lapse of Will, the slaves rose in revolt and sacked the city clean. Those slaves number some 200,000 and are armed with the best weapons and mail the fortress could yield. Their tendency to kill anything that crosses their path is a hint for the company not to seek escape from Mordor by this route.
General Notes
This map will seem a bad joke moments after game play begins. The One Ring will have been slam-dunked via the generosity of Smeagol, the Barad-dur will have collapsed into random Legos, and Mount Doom will be spewing toxins and lava enough to repave Rohan ten times over. Gorgoroth will NOT be pretty...not that it was a vacation getaway in the first place. It is vital that the GM provide constant updates on the truly hellish conditions to the north of Barad-warh at regular intervals, lest the players start to feel too comfortable.