Forgotten Keep

The Forgotten Keep was a ruined Netherese lookout tower in the southern Stonelands of Cormyr.

Location
The Forgotten Keep stood to the northeast from the town of Eveningstar, east of the Starwater River, and a shorter distance southwest of Redspring. The area was a sparsely-wooded wilderness crossed with deep stream-gullies and ravines, similar to the rest of the southern Stonelands. Helmlands

Structure
The only thing that was left of the structure by the 14 century DR was its round walls. The lookout tower's shell included a simple dwelling. Both were erected over a subterranean gate within a natural cavern that also served as a source of drinking water, refilling every spring.

Inhabitants
By the 14 century DR, the Forgotten Keep had been long abandoned and used as a lair by beasts and monsters. Bears and owlbears were known to make the ruins their home, and its cellars hid a gibbering mouther that once belonged to the wizard-master of the keep. The aberration was just one of the keep's many defenders, altered by that unnamed wizard. The gibbering mouther was granted spell-like abilities allowing it to use the underground gate to travel to new feeding spots.

In 1486 DR, the Shadovar of Thultanthar used the gate in the Keep to launch their invasion of Cormyr. This allowed Lady Marsheena's army to bypass the fortifications on Cormyr's border such as Castle Crag and High Horn, and her forces marched almost unchallenged across Cormyr to besiege Arabel, Marsember, and Suzail. By Uktar of the year, the invasion force was broken and the sieges lifted, and the War Wizards had disabled the gate in the Keep to prevent any retreat or reinforcements.