A remote coral ring in the Pacific serves as a global missile defense hub.

Countries & Cities · Published 30 September 2026 Swipe more like this →

In short: Kwajalein Atoll is more than a tropical paradise of 97 islands. Since World War II, this Marshallese territory has evolved into a high-stakes military installation, hosting a critical U.S. missile test site, GPS ground stations, and the submerged wreckage of historic vessels like the German cruiser Prinz Eugen.

Formed between 165 and 76 million years ago by volcanic activity, Kwajalein Atoll eventually subsided, leaving behind a massive coral ring that encloses one of the world's largest lagoons. Today, it functions as a vital component of the Ronald Reagan Ballistic Missile Defense Test Site. The U.S. military presence, established during World War II, persists under a Compact of Free Association with the Republic of the Marshall Islands, which maintains sovereignty over the nation.

The atoll's geography is uniquely divided. Kwajalein Island, the southernmost and largest landmass, serves as the primary base for about 1,000 U.S. personnel. In contrast, nearby Ebeye Island is a densely populated Marshallese city home to approximately 13,000 residents. While the U.S. manages defense and missile testing—utilizing specialized islands like Meck for anti-ballistic missile launches and Roi-Namur for radar tracking—the local Marshallese population remains central to the atoll's daily operations and cultural heritage.

Beyond its military utility, the lagoon acts as an underwater museum of 20th-century history. The Battle of Kwajalein in 1944 left behind numerous shipwrecks, including the 4,607-ton Akibasan Maru and the 3,535-ton Tyoko Maru. Perhaps most famously, the German cruiser Prinz Eugen, which survived the 1946 Operation Crossroads nuclear tests, rests near Enubuj Island. These remnants, alongside active telemetry and radar sites, underscore the atoll's dual identity as both a strategic military asset and a site of profound historical significance.

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