Below a deep ravine at the far end of Sippan Gulley, Texas, less than 40 miles from the Lodge, a natural-appearing stone cap some 30 feet across can slide away to reveal a circular elevator platform of unknown material that descends a cylindrical shaft 2 miles into the Earth. There it opens to an enormous cavern housing a city built by a highly advanced culture. The original Department 2 discoverers named it Murania after a famous lost culture of the ancient world (analogous to Atlantis),
Abandoned by its civilization many thousands of years ago, the city has grown a dense ecosystem of highly dangerous flora and fauna found nowhere else in the world, not all of which have been cataloged. In the 6 exploratory expeditions since its discovery in 1923, no image of its builders or original inhabitants has been found, nor any indication as to why the city was abandoned. Its architecture suggests it was built for a species very different from we bipedal, symmetrical humans.
Of the 6 expeditions, the first never figured out how to get out of the elevator shaft. Expeditions 3 and 5 disappeared without a trace, though 5 did send the elevator back up with all of their notes and samples (and survival gear).
The final expedition in 1959 aborted the mission after only 2 days for reasons left vague in the report. While ascending, something followed them up the shaft. The group decided to destroy the elevator – with them in it – rather than allow whatever it was to reach the surface. The sole survivor, John Leather, managed to climb the rest of the way out, nearly 1000 feet.
Two other “lost cities” are known to us in the US but are not under Hadden Industries control. The oldest (by date of discovery) is below Manhattan Island and is probably why the Indians sold it cheap and never came back. Secret records of expeditions to the underground city of Tawiskar (Land of Flint) as the Iroquois called it, range back to the early 1800s. The few Indian legends of journeys to the Land of Flint have been suppressed by unknown forces. Supposedly access to Tawiskar is either by tunnel connected to one of the first subways or by a mysterious underwater route.
The unnamed city in the Rockies is reached via a downward sloping tunnel rather than a shaft. The tunnel however is guarded by a 10 foot tall, highly durable robot of vaguely humanoid design.