In 1989, the same year George H.W. Bush entered office and German citizens took sledgehammers to the Berlin Wall, one married couple set out on a remarkable journey. Gunther and Christine Holtorf’s ambitious road trip was scheduled to be an 18-month jaunt through the African countryside, but it quickly became a voyage that spanned multiple continents — and decades.

When they were finished, the couple had visited 177 out of a possible 195 countries, traveled 550,000 miles, and spent 23 years on the trip of a lifetime…all from the front seat of their 1988 Mercedes-Benz G-Wagon.

Gunther and Christine Holtorf had planned for their extensive journey to take them through the African countryside. However, the road trip that was supposed to last 18 months took many, many years longer, and it brought them far beyond Africa.

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Even more unbelievable, their trip wasn’t spent miles above the ground on an airplane. No, for Gunther and Christine, there was only one way to travel: inside their beloved Mercedes-Benz G-Wagon, “Otto.”

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With the help of their trusty car, the couple left their home in Berlin and traveled the world over.

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For two and a half decades, they traveled to far-away places, from the Sahara Desert to Iraq and even, eventually, North Korea.

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To sleep, they typically spent their nights in hammocks or slumped in Otto’s front seat.

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For food, they used a gas-powered stove and ate local food. To stay clean, they showered using water bottles.

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As Gunther told Outside, “The more you travel, the more you realize how little you’ve seen. And the more you’ve seen and experienced, the more you want to continue seeing and continue experiencing.”

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Sadly, Christine passed away in 2010, but not before she and Gunther had traveled over 550,000 miles on six different continents.

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The journey was truly the trip of a lifetime.

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Gunther, for his part, kept the voyage alive and decided to visit a few more countries after Christine’s death — all with a photo of his beloved wife hanging from the rearview mirror.

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At long last, and at 76 years old, Gunther’s road trip brought him back to Berlin, this time for good.

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Though his days on the road have ended, he’ll always have the memories of a life — and marriage — well lived.

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They really might be the greatest travelers ever! Learn more about how they did it in the video below.

Gunther actually credits “Otto” for most of the trip’s success, saying that, “the sturdiness and reliability of this car is absolutely astonishing.” After never once breaking down, Otto will be retired at the Mercedes museum in Stuttgart, Germany. Gunther, meanwhile, may continue on without his trusty vehicle: he still hopes to travel to the few countries he has yet to see!

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