This is the lair of Nozdormu—the Dragon Aspect of Time, as mentioned in Warcraft: Day of the Dragon novel. It is southeast of Gadgetzan in Tanaris. Nozdormu is one of the five dragon aspects. A titan blessed him with the aspect of Time.
Nozdormu is known to be obsessed with collecting artifacts from different time eras. The bronze dragonflight monitors different alternate realities as revealed by Chromie in Andorhal(Western Plaguelands).
As has been revealed, despite the attempts of Nozdurmu and his dragonflight, the gateway into Azeroth’s past will be opened through the Caverns of Time. Venture to the Black Morass?? and witness firsthand, the creation of the Dark Portal. Travel through Hillsbrad and into Durnholde Keep as a young orc slave named Thrall first starts on his path towards destiny as Warchief of the Horde.
Visit the World Tree Nordrassil at Mount Hyjal in the recent past, as the races of Azeroth rally to fight and defend it from the demonlord Archimonde (Warcraft III: Reign of Chaos)—fight alongside Thrall, Malfurion and Jaina Proudmoore against the Burning Legion and its Undead Scourge.
Travel back in time 30 years into the past, and witness the opening of the Dark Portal when Medivh—under Sargeras influence—calls forth the Orcish Horde into Azeroth.
Fight beside Khadgar’s Alliance Expedition Force in the Hellfire Peninsula against the Orcish Clans during the Second War (Battlegrounds)—read the Campaign missions of Warcraft II: Beyond the Dark Portal.
The possibilities are truly endless when you can tread back into time.
Expect to experience these exciting possibilities when World of Warcraft: The Burning Crusade Expansion is released.
?? Black Morass was formerly Swamp of Sorrows and Blasted Lands. Blasted Lands was part of the Swamp, but the energies of the Dark Portal and the Warlock and demonic magic drained the life off the surrounding area turning it into a redish clay. The same fate of Draenor’s terrain.