|Global Tunnel System|
The Montauk using Nod's Tunnel System
Subterranean transport network
By the time of the Third Tiberium War, the proliferation of underground Tiberium deposits have rendered these tunnels unusable. However, not only did the Tiberium Control Network made it safe for the Global Tunnel System to be used again, but it also added more tunnels due to the TCN removing Tiberium from underground and the surface, leaving hollow cavities in their place that was then used by Nod during the Ascension Conflict.