The Airplane Room: Deep Under Cumberland Mountain

The following entry was written by a guest author who wishes to be known only as The Mysterious Man from Rose Hill. We’ve decided to name this huge underground cave “The Airplane Room” in memory of his father.

This is a story that was told to me by my father when I was 8 to 10 years old in the late 50’s. It was an exciting story for a young boy and I still have vivid memories of him telling it.

Please understand that everything I’m relating is hearsay as I have no way to verify or corroborate the account. My father was a very truthful person. In fact he would often admonish me as a child to never exaggerate or embellish a story. “If you stretch the facts, then no one will believe you when you do tell the truth,” he said.

Following is a recounting of the story as told by my father, as  I remember it:

The setting is in Cumberland Gap, Tennessee where my father lived with his family. The time is the early 40’s. It was the war years, and my Dad was in his early teens.

One night, Dad and two of his friends decided to go exploring in Gap Cave, known at that time as Cudjo’s Cave. Arriving late at night, after everyone had gone home, they entered the cave and began their exploration to see how far they could travel inside the cave. After making their way through rough terrain, narrow passages, small openings, mud and water for nearly half the night, they were surprised to enter a huge room much larger than anything they could have imagined.

“We were so excited to have made this amazing discovery,” Dad said, “And to think we were the first people to see it.”

I said, “Dad, how did you know that you were the first people to discover it? How did you know no one else had been there?”

He said, “Well, when we first went in that big room, there was water dripping everywhere. The water had puddled on the floor, and on top of the water, minerals had hardened like a thin sheet of ice on a pond. Where we walked, we broke through the crystal, just like breaking though thin ice, and it left our footprints visible. When we first went in, there were no other footprints, so we knew we were the first.

“Dad,” I said, excited, “just how big was this room? How many feet across?!”

“I don’t know exactly,” he said, “we didn’t have anything to measure with, but I know how big a football field is, and you could put several in it.”

“How many?” I asked.

“Well, several, ” he said.

“Dad, could you see all the way across from one side to the other? Was the ceiling high enough to see the walls all the way around?”

“Oh yeah, he said, “it had a high ceiling.”

“How high would you estimate?”

He said, “Well, it was high enough that you could fly an airplane around in it!”

“Dad,” I asked, “could you fly a passenger plane in it?”

“I don’t know about that,” he said, “but there’s plenty of room to fly a small two-seater plane around inside!”

“Could a small plane take off in that room?” I asked.

“No,” he explained, “the floor is not smooth enough. There are big boulders strewn across the floor. We thought that, in time, there must have been an earthquake and part of the ceiling must have fallen.”

“Do you think that room might ever be open to the public?”

“I doubt it,” he said. “It’s too far back in the mountain and too hard to access. Some of the openings are very small.”

“How long were you there exploring?”

“Not too long,” he replied. “It was a long trek to get there, and we had to be out before morning.”

“Dad,” I asked, “did you carve your names and a date, so people would know you were there?”

“No, he said, “we didn’t do that.”

“Dad, if I ever had a chance to explore that cave, is there any way I could know you were there?”

“Well…” he thought, “we did leave one thing behind. We noticed how heavily everything was mineralized, and we wondered how long it would take for the mineralization to occur. We left a coke bottle under a dripping stalactite thinking that we might come back some day.”

“Dad, how did you get inside the cave?”

“Well,” he said, “there are several ways to get in, but that’s a story for another time, and I have a hard day tomorrow. It’s bedtime and we’d better turn in.”

Nazi Germany, Vemork, and Cumberland Gap

Screenshot 2015-04-13 23.53.37What do the Nazis, a Norwegian hydroelectric plant, and the saltpeter caves of southwest Virginia (including Cudjo’s) have in common?

The ability to make heavy water.

Water contains hydrogen. Normally, the hydrogen in water contains no neutron in its makeup, just a proton. Heavy water, however, contains hydrogen that has the added “weight” of a neutron in addition to the proton, hence the name “heavy water.”

Deuterium is another name for heavy water.

During WWII, Allied forces learned of Nazi interest in a Norwegian hydroelectric plant that also produced fertilizer (specifically, calcium nitrate, or saltpeter). Heavy water, or deuterium, was a by-product.

To Norwegian Resistance fighters during World War II, heavy water was a mysterious substance considered so perilous that they were willing, under orders from the Special Operations Executive in London, to sacrifice the lives of their countrymen in order to keep it out of Nazi hands.  – (1) PBS, Nova, “Hitler’s Sunken Secret”

The Allies surmised the Nazis wanted the factory for its by-product of  deuterium, which is critical to creating weapons-grade plutonium-239.

I believe the United States knew of the potential of creating fertilizer with hydroelectric power when the national defense act of 1916 went into effect.

Col. J.W. Joyes…was instructed to inspect sites [for the location of the nitrogen/fertilizer plant] extending from Roanoke, VA., to certain Alabama sites…(2) 66th Congress, Second Session, War Expenditures Ordnance

The nitrate supply committee recommended this to the 66th Congress:

That the construction of the initial plant be started at once at some point to be selected by the War Department in southwest Virginia or adjoining territory in West Virginia reasonably near to the sulphur, sulphuric acid, and coal supplies of that region. (2)

The hydroelectric U.S. Nitrate plant was eventually built in Sheffield, Alabama with the help of a Norwegian named Berg. (I suspect it is the same Berg who would later be associated with the Vemork plant in his home country.)

Clearly the experts thought President Wilson was misguided when he chose the Alabama location:

Why the President selected the site at Sheffield Ala., for nitrate plant No. 1, contrary to all reports and recommendations, is not known. (2)

I think the President chose Sheffield Ala. to direct attention away from the southwest Virginia saltpeter caves and the real work of munitions production. He visited Lincoln Memorial University in 1918 under the guise of receiving an honorary law degree. (8) It’s certain the trip was actually a visit to the saltpeter/nitrogen operations in Cumberland Mountain, a few short miles away.

It is important to note that TVA was successful at large scale fertilizer production in the Alabama plants (see Dr. Jeremy Whitlock’s statement near the end of the blog post.)

Below describes the way limestone is used to help manufacture saltpeter:

[Nitric] acid can be neutralized with ammonia to form ammonium nitrate or with calcium hydrate to form calcium nitrate (Norwegian saltpeter).


 …we allow the acid to pass through open towers, filled with limestone, and afterward we destroy the small amount of remaining acid….  (3) Chemical and Metallurgical Engineering, Vol. 24

According to the above journal, this process takes 15,000 tons of limestone, 500 tons of lime, and  2500 tons of soda to produce 29,000 tons of saltpeter.

The November 2001 issue of Virginia Minerals “Geology and History of Confederate Saltpeter Cave Operations in Western Virginia” states:

In the 1860s the southern war machine benefited immeasurably from the conditions of climate, vegetation and geology that gave it the greatest concentration of saltpeter cave deposits in North America. (4)

Luckily for the U.S. Government limestone was abundant in western Virginia as well:

Cumberland Mountain has an extensive limestone cave system on the Virginia side. – Sherpa Guides, “Highroad Guide to the Virginia Mountains” (5)

But the government struck a home run when they discovered a small college named Lincoln Memorial University already had a hydroelectric plant deep inside one of these limestone saltpeter caves: Cudjo’s Cave.

…an active stream runs inside the cave, and was harnessed for drinking water and hydroelectric power. – (6)

It is unknown if it is the same hydroelectric plant mentioned in the 1911 edition of Southern Electrician:

Plans are underway for the erection of a hydro-electric plant for the purpose of supplying power to manufacturers near Cumberland Gap. The plant will be located on the Cap creek.(9)

It is not known if “Cap” is a misspelling of “Gap”.

All three elements needed to produce deuterium are located right here in southwest Virginia: the naturally thriving saltpeter, a catalyst (limestone) that would replenish and produce even more, and the power of hydroelectricity.

I asked Dr. Jeremy Whitlock, a Canadian reactor physicist with decades of experience, how the massive amount of heavy water needed for pressurized heavy water nuclear reactors, or PHWRs, is produced today:

In the future if industrial-scale production is needed again (and I hope it is), we will likely use a catalyzed exchange process attached to an existing process based on electrolysis or hydrogen reformation (e.g. fertilizer production). (7)








7. Personal email, April 9 2015; copies available upon request




Cudjo’s Cave, Cumberland Gap Tunnel, and World Events: A Timeline

UPDATED April 11: the date of 1942 added to reflect the Allied forces discovering the Nazis using saltpeter to make heavy water for nuclear bombs in Norway.

1740- Caves in the western portion of Virgina are mined for saltpeter, also known as nitre, a crucial ingredient in gunpowder

1765-1783 and 1812-1815- The American Revolution and War of 1812. The saltpeter caves in Virginia continue to be a valuable source of nitre needed for the war efforts

1815-1860- Consumption of western Virginia nitre increased so much the caves could no longer keep up: the state had to import nitre to satisfy the demand

1861-1865- The Civil War. If nitre production was going to be profitable for Virginia and the Confederacy in the war effort, they had to find more saltpeter caves and invest capital in their development.  The Confederacy established the Nitre Corps (which became the Nitre and Mining Bureau) to this effect. Their efforts were successful; Virginia nitre production easily kept up with the military demands.

NOTE: Because of their deep underground location, the scattered saltpeter caves were valued by the Confederate military, as they proved to be an elusive target for enemy forces. (1. Virginia Department of Mines, Minerals and Energy)

1920- Lincoln Memorial University in Harrogate TN purchases Cudjo’s Caverns (one of the Virginia saltpeter caves) from private owners, including the caves known as Soldiers Cave and King Solomon’s Cave.

Although originally separate caves, these two caves “were connected by a passageway and a larger main entrance by blasting and tunneling” although the date this connection was accomplished is unknown. We do know the caves remained separate at least as late as 1937. (2. Thacker, 212)

1939- World War II begins

1940- Congress authorizes the acquisition of land in the Cumberland Gap area for Cumberland Gap National Park, only after language is omitted from the Act calling it a “recreational area” (3)

1941- Pearl Harbor attacked, the United States enters WWII

1942-Allied Forces discover a Nazi-occupied Norwegian hydroelectric plant that also makes fertilizer out of saltpeter. They discover the real purpose of this plant: the production of heavy water, an essential component of nuclear weapons.

-the start of the Cold War

-the title to Cudjo’s Cave (also known as Saltpeter Cave) is signed over to the state of Virginia and eventually transferred to the federal Park. Originally, the saltpeter cave was a separate holding within the National Park.

1954- a Masonic lodge, Martin’s Station Lodge No. 188 opens 1000 feet below Cumberland Mountain in Cudjo’s Cave. 345 Masons are present for the conferring of a Master Mason degree. (4)

1955- Although acquired in 1940, the Park was not opened to the public until 15 years later in 1955. (5)

1972- in November, hijackers threaten to crash plane into the Oak Ridge nuclear complex in Tennessee (6)

1973- Congress tells the National Park to construct the tunnels under Cumberland Gap (5)

1990 to 1991-  The Gulf War (Operation Desert Shield) begins, leading to Operation Desert Storm
– Construction of the Cumberland Gap Tunnel begins (5)

1992- the federal government closes Cudjo’s Caverns to the public indefinitely

1996- the Cumberland Gap Tunnel opens. The road to Cudjo’s Cave and over Cumberland Gap is removed soon after.(5)

It is 2015, and only recently did the Park start allowing very limited access to Cudjo’s Cave. See my post here about Cudjo’s Cave.


The federal government has had a keen interest in the saltpeter caves of western Virginia (including Cudjo’s Cave) from the 1700’s. As our government becomes less transparent, it’s hard to ignore the coincidental timing of Congress to act on the development of these caves, the Cumberland Gap area and the Cumberland Gap Tunnel in relation to world events, specifically military conflicts.

Coincidence? Or conspiracy?

1. Virginia Department of Mines, Minerals and Energy;

2. Mountain Mysteries: The Mystic Traditions of Appalachia; Thacker, Larry. 2007

3. Cumberland Gap National Historic Park; Luckett, William. 1964

4. “York Lodge No. 22 Bulletin”; 2010

5. “Cumberland Gap Tunnel marks fifteenth anniversary”; Simmons, Morgon. 2011

6. “Convicted hijacker  shares story; details 1972 threat to Oak Ridge”; Welsch, Anthony. 2011


The Cumberland Gap Tunnel: One big, fat anomaly

Cargo bays run end to end in Cumberland Gap Tunnel

Cargo bays. A lot of them. Lining the entire length of the tunnel, separating the north and south bound lanes. According to former workers they are rooms, and in these rooms are more doors, leading from one room to the next. It is not a simply a hallway between two ends of a tunnel like you might think.

The ceiling of the southbound side of the tunnel is significantly higher than the north bound side. Is it to accommodate larger military vehicles? Could the tunnel be some kind of “flight deck” or loading zone for fast, efficient loading of arms, even nuclear arms, on military vehicles in times of conflict?

mysterious doors in the tunnel lead deep into cumberland mountain

Little is known about these doors as current employees of the tunnel are forbidden to enter.

Former workers that helped build the tunnel say the door on the right of the northbound lane leads you to the water pouring down inside the mountain that makes up the lake the tunnel is supposedly built over.

The door on the right in the southbound lane leads you to the underground lake itself. This lake has no measurable depth. The former workers weren’t sure of it’s surface area either, for a miner’s headlamp shone across the waters would still not reveal an opposite shore. In other words, it’s big.

Still another door opens to another passage leading into the mountain above the southbound lane in the second story of the tunnel in what I refer to as the administrative section of the tunnel:  the office-and-lobby-type areas behind the big glass windows. No one has any information about this passageway, other than the door is often propped open at night, visible when you are entering the northbound side of the tunnel toward Kentucky.

Other than this information, no one knows how much farther these passageways lead into the mountain, or their ultimate destination.

Extensive security cameras in place designed by former Oak Ridge National Laboratory scientists

Ipix is a Tennessee company that makes surveillance cameras capable of projecting 360-degeree panoramic images. This company was founded in Oak Ridge by former scientists from the nuclear laboratory. These scientists’ company initially started working with “recording robots” for use in nuclear plants. But the invention of their PhotoBubbles and 360-degree camera surveillance put them at Cumberland Gap Tunnel, in what they describe as “mission critical imaging”.

IPIX Security is the leading supplier of Full-360 degree video surveillance technology for critical government and commercial security applications.


IPIX Security is a division of IPIX Corporation, a leader in mission critical imaging.

Congressman Wamp called the tunnel a “critical part of our nation’s infrastructure” and the reason why the expensive, high tech cameras were needed. If this is true, then how much more critical are the tunnels located on major interstates like I-40 and I-77?  Yet these tunnels have no security cameras, let alone state-of-the-art cameras invented by nuclear scientists from the Secret City.

Hazmat escorts that seem more for the tunnel’s protection than ours

They make hazardous materials trucks, like gasoline tankers, pull off for private escort when both sides of the tunnel are open and operating normally.

They send the same hazmat trucks through the tunnel with regular traffic when they are working on one side of the tunnel. This destroys the logic that they make hazmat trucks stop for escort for our protection.

Not only do the hazmat truckers have to stop for escort through the tunnel 99% of the time, their records and logs are carefully checked by tunnel personnel while they are waiting.

Trucks that display a hazardous material placard are required to stop at the Cumberland Gap Tunnel inspection lanes. After stopping in the lane, a CGTA operator requests information from the driver such as Trucking Company name and address, DOT #, Truck license #, Truck Order # or bill of lading, origin and destination of goods, and driver’s name and signature. The operator then performs a walk around inspection of the truck and looks for possible hazardous material leaks. Trucks transporting Class 1 Explosives are prohibited and are turned around at the tunnel.


In retrospect, it almost seems like a security checkpoint. For a tunnel on a highway most people in the United States have never even heard of.