Inside Seven Military Bases That Are So Secret You've Probably Never Heard Of Them

Villainous hideouts are a hallmark of the James Bond universe. Whether nestled deep within a mountain, perched on a remote island, or housed in an unusually shaped building, they add an air of mystery to the clandestine activities within. Surprisingly, there are several real-life secret military bases that mirror these descriptions - and you probably haven't heard of them. Here are seven of them.

Cheyenne Mountain Complex

Located in the heart of Colorado, the Cheyenne Mountain Complex was once home to the US Space Command (USSPACECOM) headquarters and the North American Air Defense Command (NORAD). It was constructed during the Cold War , in an effort to use the natural exterior of the granite mountain as a defense against Soviet aerial and nuclear attacks.

The mountain was hollowed out by the US Army Corps of Engineers, and became fully operational on February 6, 1967. Upon its completion, the site was used to monitor threats to Canadian and American airspace, including foreign aircraft, missile attacks and space systems.

In 2008, the tracking done at the Cheyenne Mountain Complex was moved to the nearby Peterson Space Force Base . While still in service and under the care of the 21st Mission Support Group, this secret military base is now used to train crewmen and operate as a backup site, should it ever be required.

US Army Garrison Kwajalein Atoll

During the Second World War , the US performed an amphibious landing on the island of Kwajalein and never left. There were Japanese troops stationed there who were either captured or killed. A secret military base was established there as the conflict drew to a close, acting as a staging area for Operation Downfall - the planned invasion of the Japanese homeland.

Instead of giving up the island when the war ended, the Americans stayed and established it as one of their command centers for nuclear testing in the Marshall islands. As a result, much of the local population was pushed out, and those who remained worked in labor camps.

With the end of the Cold War, much of the nuclear testing was canceled and the size of the US Army Garrison drastically shrank. That isn't to say that they left completely, as there's still a military presence on the island. In fact, the Americans have it leased until 2066.

At present, Kwajalein atoll is home to the Space Fence radar, which is used to track space debris and satellites. It's also one of five ground stations used to control GPS technology.

Yulin Naval Base

Yulin Naval Base, operated by the People's Liberation Army Navy, is perhaps the most mysterious location on this list. Very little is known about this secret military base, as it's located along the coast of Hainan Island, in the South China Sea. Much of what is known comes from open-source intelligence or satellite images, including that construction began sometime around 2000 . It's also believed the base isn't yet finished, as two new docks were under construction as of 2022.

Yulin Naval Base has both above- and below-ground docks for submarines, and satellite images have shown weapons being loaded onto them - although what kind and how many remains a mystery. While warships are able to dock there, the primary purpose of the base is to house nuclear submarines, which can - and do - travel into the semi-submerged mountainside tunnel entrance.

Porton Down

Porton Down, still in operation today, is the world's oldest chemical warfare research facility. It's also incredibly controversial. Located in Wiltshire, England, Porton Down began as the War Department Experimental Station in 1916 and opened in response to the German use of chemical weapons in World War I . Those employed there were tasked with researching possible solutions, as well as improving respirators.

Although it remained open during the interwar period, this secret military base was, again, fully staffed during the Second World War, when the research focused on studying newly-discovered German nerve agents and creating British biological weapons. The main criticism of the establishment was that the tests all took place on human subjects - so-called "volunteers" - who were conned into participating. Many died or suffered long-term health consequences from the tests.

Still in operation, Porton Down holds samples of many deadly pathogens, including anthrax, the Black Plague and Ebola. Those who work there are still active in analyzing mysterious chemicals, viruses and pathogens.

Naval Support Facility Diego Garcia

Naval Support Facility Diego Garcia is a secret joint military base run by the British and Americans, situated in the Indian Ocean. Established in 1971, the facility was built following the forced relocation of the native Chagossian population. Originally, it hosted 20 deepwater logistics ships, but later, a naval airfield was established and operated from 1981 to 1987.

Despite its remote location, 1,000 miles from India, Naval Support Facility Diego Garcia has been crucial on numerous occasions. During the onset of the Iraq War , it provided essential logistical support. Until the Americans could set up their own bases on enemy territory, the island served as a critical site for aircraft operations.

In recent years, the facility has gained importance for tracking satellites and deep space objects using Ground-Based Electro-Optical Deep Space Surveillance systems.

Pine Gap

This secret military base, located in the Australia Outback , is certainly a sight to behold, with its large white spheres. It's jointly operated by Australian and American forces - including the Central Intelligence Agency (CIA), National Security Agency (NSA) and the National Reconnaissance Office.

Despite its remote location, Pine Gap plays an extremely important role in international reconnaissance and intelligence. It's the control center for many spy satellites, which travel over Russia, the Middle East and China. In fact, the site was chosen specifically because it's too far away for these signals to be intercepted by spy ships.

Pine Gap was opened in 1970 and initially designed to focus on detecting nuclear threats and Soviet missiles during the Cold War. It has now moved toward supporting the US military by detecting airstrikes, as well as intelligence and data gathering.

Volkel Air Base

There are only three places in the world that don't show up on Google Maps, including the last entry on our list of secret military bases: Volkel Air Base. It's not exactly clear why it can't be found, especially as it's easily located by those living in the area. The most popular theory is that it has stored weapons for the US Air Force since the Cold War. This hasn't been commented on by the Dutch Minister of Defence, but leaked documents indicate there are these types of weapons in the Netherlands.

Volkel Air Base was actually created by the occupying Germans in 1940, first for use as a diversionary base for Allied bombings, and, later, as a fully-operational Luftwaffe base. Following Allied attacks on the airfield as part of Operation Market Garden , the Germans were no longer able to use it. The Royal Air Force (RAF) briefly did, however, after they gained control of the area.

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In 1949, the base was used by the Dutch Naval Aviation Service (MLD) for training, before being restored to a functional airfield by the Royal Netherlands Air Force (FNLAF) a year later. It's still in use today, and may or may not have nuclear weapons.