A country's military has long been used as an indication of a country's power and influence. Countries pour billions (even trillions) of dollars into their military in order to acquire the best training, the best weapons and, quite frankly, the best everything!

When people think of a powerful military, they usually think of the USA. The country spends more money on the military than education, healthcare, and social services combined. However, they are not the only ones who have put effort and resources into their military.

Military bases are the center of an army's training regiment, research projects, and strategic plannings. And some of them are straight-up epic to look at. Here are ten military bases that are impressive (and more than a little intimidating).

10 CIA's Eye In The Sky: Joint Defence Space Research Facility Pine Gap (Australia)

This sprawling base, while it's based in Australia, is run by the CIA, NSA, and NRO. There are 38 radomes (the large white golf ball structures) that control spy satellites that cover China and the Middle East. Their strategic placement in Australia helps with avoiding counter-intelligence from capturing any signals.

9 Communication Advantages: Duga-3 (Ukraine)

This Russian military base is known for its massive antenna (affectionately nicknamed the Russian Woodpecker). It was used during the Cold War as part of the Soviet's powerful over-the-horizon radar (OTH). The sound that is created was heard on shortwave radio bands was a constant between 2976 and 1989.

8 Retired Military Airport: Eareckson Air Station (Aleutian Islands)

This airport was renamed the Eareckson Airport to commemorate Colonel William O. Eareckson, who was involved in high-risk missions against Japan during the Second World War. While it stopped active military activity in 1994, it is still used for refueling purposes, as well as a diversion airport for civilian airplanes.

7 A Nazi Remnant: Saint Nazaire Submarine Base (France)

Saint Nazaire was created by the Nazis during the Second World War. It's most known for being the site of a historic aquatic raid by the British army known as the "St Nazaire Raid". Since demolishing it was too expensive and difficult, it was turned into a cultural site.

6 Radioactive Hot Spot: Johnston Atoll (USA)

While this area currently belongs to the United States Fish and Wildlife Service, it was a military base during the Vietnam war. In the early sixties,  there were many nuclear bomb launches performed here. Agent Orange and mustard gas were also stored on the island. Talk about being radioactive!

5 An Indestructible Fortress: Flak Towers (Austria and Germany)

During the Second World War, the Nazis kept themselves busy building anti-aircraft gun blockhouse towers throughout Hamburg, Berlin, and Vienna. Because of their architecture and fortifications, demolition has proved nearly impossible, while repurposing them has also proven less than straightforward. Today, they stand as remnants of a defining moment in history.

4 Used For Military Advantage: Olavsvern Naval Base (Norway)

Talk about blending into your surroundings! Norway created this naval base during the Cold War, with the goal of secrecy. To achieve this, it was carved into a mountain and cost 4 billion Kroner (541 billion CAD). After no longer having a need for it, NATO approved its decommissioning.

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3 U.S. First Line Of Space Defense: Thule Air Base (Greenland)

This airbase, hidden away in the arctic region of Greenland, serves as the base camp for a global network of sensors that detect missile launches, as well as space surveillance. It has been the home of many military groups of projects with the goal of protecting North America against missile attacks.

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2 Still Carries History Inside It: Zeljava Underground Airbase (Croatia)

The construction of this military base was one of Europe's largest and most expensive military construction projects. And remnants of conflicts are still active within the base. There are plenty of mines and bombs left over from the Yugoslav Wars. As a result, it is off-limits to tourists.

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1 Became Its Own Micro Nation: Maunsell Sea Forts (North Sea)

These strange little pods aren't exactly a military base, but they were used during the Second World War to defend the United Kingdom against submarine and aquatic attacks. Even cooler, they used to be part of a micronation called Principality of Sealand. They even had their own currency and stamps!

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