Northern Lordaeron



Northern Lordaeron is an unofficial name used to refer the unnamed closed zone wedged between the northwestern border of the Eastern Plaguelands, the northeastern border of the Western Plaguelands, and the southwestern border of the Ghostlands. Currently it is an inaccessible zone in-game that may be part of the fallen Kingdom of Lordaeron or of the Kingdom of Quel'Thalas. Also this is the place where the Thondroril River is born geographically.

Speculation
The architecture of the area (a tower, a dock, and a few other buildings) is curiously based from night elven designs found in Darnassus and Teldrassil, perhaps implying that the high/blood elves made use of it prior to founding their own culture in Quel'Thalas. It is important to note, however, that these buildings have been present since the game's initial release before Quel'Thalas even existed in-game.

This could be the land that Daval Prestor (a human disguise used by Deathwing) claimed to have originated from during the Second War as he was described as being from the north of Lordaeron.

This could be the land of the "northern vassals", whom Terenas's grandfather helped in their negotiations over their borders with the elves of Quel'Thalas.

Cataclysm
Due to the revamping of Azeroth to accommodate flying mounts, the area has been textured and sparsely filled in with mountains and grass. However, an invisible wall has been placed all around the zone, so that is now impossible to reach it in any way, flying included, unless exploited.

Other information
According to the roleplaying guide, a number of high elves who did not become blood elves took refuge on some lands in the north of Lordaeron and adjacent to Quel'Thalas. This could be that location. In fact, Quel'Lithien Lodge is a town of high elves that is located adjacent to Northern Lordaeron in the Eastern Plaguelands and into the closed area, there are some elven ruins, indicating the presence of high elves in this zone.