From Dragon Age wiki
Deep Roads
The Deep Roads are an ancient, subterranean network of tunnels spanning beneath the continent of Thedas, originally constructed by the dwarves to connect their vast underground empire.
History and Construction
Originally carved out by the dwarven kingdom of Orzammar, the Deep Roads once spanned the entire continent of Thedas, allowing for rapid travel and trade between the various thaigs. At the height of dwarven power, these tunnels were a marvel of engineering and stonecraft, serving as the backbone of their society. However, the expansion of the network eventually led to the discovery of the darkspawn, triggering the First Blight and leading to the abandonment of many thaigs.
Current State
In the current era, the Deep Roads are largely overrun by darkspawn and remain extremely dangerous for any surface-dweller or dwarf to traverse. While characters like Oghren are intimately familiar with the perils of these tunnels, they are now primarily viewed as a source of constant threat rather than a trade route. Expeditions into the depths are often undertaken to recover lost artifacts or to push back the darkspawn tide, though few return unscathed from the subterranean darkness.
