Depths of Tyria
The Depths of Tyria is the name of the subterranean network of caverns and tunnels that run beneath the surface of Tyria. Many of the structures and tunnels found in the Depths predate humanity in Tyria and their origin is unknown. 250 years ago, the Depths were inhabited by many subterranean races such as the asura, the skritt and the dredge, who now live above ground or much closer to the surface world. These races were forced to abandon their previous homes because of the Elder Dragon Primordus and its Destroyer minions, who now occupy the Depths, still being held back by the stone dwarves.