Ronneberg, second from left, shaking hands with the king of Norway. Wikipedia photo.

The last living member of the successful raid that deterred Hitler's nuclear program, Joachim Ronneberg, died last week at the age of 99. Ronneberg didn't set out to be a hero when he volunteered to join the Norwegian resistance during World Word Two, yet he managed to change the course of the war.

When the Royal Air Force launched an all out assault on a Nazi nuclear research facility in Norway and came up short, their only backup plan was to drop a team of nine skiers, led by a 23-year-old Ronneberg out of an airplane. In a blizzard. 40 miles from their target. The group made those 40 white and somber miles on cross-country skis through the Telemark region of Norway under the cover of darkness.

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Once they reached the valley where heavy water, a key ingredient in the making of an atomic bomb, was being produced they realized that the narrow suspension bridge they had originally planned to cross was guarded by armed men 24 hours a day. The surrounding area was also full of landmines which were completely covered by snow, thanks to the blizzard.

The Vemork Hydroelectric Plant, which the group rendered useless by destroying the heavy water production cells. Wikipedia photo.

After some deliberating, the men decided the best and likely only way to complete their mission was to scale down a 500-foot cliff in the middle of the night. Clutching branches and shrubs, the group descended, reached the river below, and crossed on an ice drift. Above them the guards went about their business on the bridge.

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On the other side of the river the men clambered up a snowy bank and prowled along a railway track until they reached the plant’s fenced perimeter. Using shears he bought in a London garden store, Ronneberg cut the metal fence and made his way in. All doors inside the facility were locked, but the team located an air duct that was just big enough to squeeze through. With backpacks full of explosives, the men crawled through the vents and eventually came to what they deemed to be the heavy-water production center.

D/F Hydro, a ferry that was used to transport nuclear materials, was sunk by Norwegian resistance. Wikipedia photo

The team loaded the water tanks and cylinders with their explosives, lit the fuse, and ran out. Before they had even crossed the river, the sound of an explosion was heard and shortly after that the sound of an alarm. A massive Nazi manhunt ensued, but one that was ultimately futile. Joachim Ronneberg led all nine of his men safely back to Sweden where he was recognized as a hero, and Hitler never got his atomic bomb.