The name of this zone is commonly abbreviated in chat as DP.
For Asmodians, access to this zone is via the Artifact of Circulation at Hoarfrost Shelter in Beluslan.
For Elyos, access to this zone is via the Artifact of Transcendence on the hill next to Kishar Observation Post in Heiron.
There is a third artifact/entrance, open to all, by the Divine Fortress in the Eye of Reshanta.
Patch 1.9 increased the drop rates for the boss monsters in this zone.