Known as America’s “Last Frontier,” Alaska conjures up thoughts of polar bears, subzero temperatures and expansive areas of little-explored terrain around the Arctic Circle.

Alaska’s often harsh environment makes year-round living difficult at best, with some areas accessible only by boat or aircraft.

The state is more than double the size of Texas with a population about the size of Washington, D.C.

Yet despite the geographic and environmental challenges, the U.S. military has staked its claim there since the 1860s, when the U.S. bought the territory from Russia and nearly a century before Alaska became a U.S. state.

In the last decade, the military has redoubled its efforts in the far north, investing billions of dollars upgrading air and missile defenses while completely revamping the foundational structure of its Army forces.

At Eielson Air Force Base, near the Arctic Circle, the Air Force just added 54 of the nation’s new F-35 stealth fighter jets. The jets, perched at the top of the world, are prepared to respond to conflicts anywhere in the northern hemisphere.

The base operates year-round, even in skin-burning minus 50-degree weather, when airmen can withstand the frigidity for only minutes at a time.

In warmer weather, the base hosts multiple Red Flag Alaska exercises: war games for thousands of American troops to train in combat-like situations with allies from around the globe.

At Clear Space Force Station, about 160 kilometers southwest of Eielson, the U.S. Space Force, Alaska Air National Guard and members of the Missile Defense Agency monitor threats in space, including North Korean intercontinental ballistic missile launches.

In December, the Clear station team received a new tool in their missile-tracking arsenal, the Long Range Discrimination Radar, or LRDR, which officials say is the most sophisticated ground-based radar on the globe, capable of seeing farther than other ground-based radars while simultaneously differentiating among multiple small objects.

At Fort Greely, an Army garrison about 120 km south of Eielson, a team of soldiers protects 40 ICBM-killing weapons known as Ground Based Interceptors in silos deep underground. The U.S. recently added 20 silos there, which will house new and improved anti-ICBM weapons known as Next Generation Interceptors around 2028.

At the Army’s Fort Wainwright, near the Arctic Circle, and Joint Base Elmendorf-Richardson near in the state’s largest city, Anchorage, soldiers this month were assigned a new identity, transforming from a hodgepodge structure under the U.S. Army Alaska flag to the newly resurrected 11th Airborne Division. The “Arctic Angels,” as they’re called, vow to “regain” American dominance in the Arctic.

VOA visited each of these military locations to get a first-hand look at the new upgrades in action, hidden in plain sight deep within the remote Alaskan wilderness.