The strategic Baltic island that survived centuries of conflict and shifting borders

Nature · Published 30 September 2026 · Updated 25 October 2026 Swipe more like this →

In short: Bornholm is a landscape of dramatic granite cliffs and sun-drenched figs, but its history is anything but peaceful. From medieval fortresses to Soviet landings and Cold War radar bases, this Danish island has been a high-stakes prize for empires for centuries.

Geologically, Bornholm is a 'rock island' defined by granite formations that store summer heat, creating a microclimate warm enough to support the 'Bornholm's Diamond' fig. This topography stands in stark contrast to the rest of Denmark, which is characterized by gentle, rolling hills. The northern landscape is marked by dramatic cliffs, while the south is defined by sandy beaches.

Because of its strategic location in the Baltic Sea, the island has been a contested territory for centuries. While usually ruled by Denmark, it has been held by Sweden and Lübeck. A significant moment occurred in 1658 when the Treaty of Roskilde ceded the island to Sweden; however, a local revolt led to the inhabitants handing the island back to the Danish kings in 1660.

The island's 20th-century history was equally turbulent. In 1942, a dummy V-1 flying bomb crashed on the island during testing, providing British Intelligence with early evidence of German rocket aspirations. During the final stages of WWII, Soviet troops landed on the island in May 1945, leading to a short fight and the surrender of a German garrison of approximately 12,000 men. Following the war, the island served as a critical Cold War radar base for monitoring Soviet and East German activity.

Today, the island operates with a unique level of autonomy. Due to its remote location, the Bornholm Regional Municipality functions almost as its own region, managing its own traffic company, BAT, and performing various administrative tasks typically handled by larger Danish regions.

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