A 59-year-old German man is celebrating after breaking the world record for the longest period living underwater without depressurisation. The secret? Good wine.

German man lived underwater for 120 days

After 120 days, a German aerospace engineer has broken the world record for the number of days living underwater without depressurisation.

59-year-old Rudiger Koch of Baden-Württemberg lived in a 30-square-metre capsule submerged off the coast of Panama from October 2024 to January 2025.

15 minutes by boat from the Panamanian coast, Koch’s capsule was submerged 11 metres below the surface and connected by a narrow spiral staircase to a chamber floating on the ocean’s surface. 

While Koch stayed underwater for 120 days, helpers brought food to him below the waves, a doctor was on site and 24 / 7 surveillance cameras ensured he stuck to the conditions required to break the record. The underwater cabin was fitted with a bed, TV, toilet, exercise bike and internet, but didn’t have a shower.

When Koch re-emerged he broke the previous record for living underwater, 100 days endured by US biomedical researcher Joseph Dituri in 2023.

Underwater record holder was inspired by Jules Verne

Speaking to the dpa following his record, Koch said his flannel wash bathing technique below deck “felt like something from the 19th century”.

The record holder has admitted to being a fan of Jules Verne’s 1870 novel Twenty Thousand Leagues Under the Sea, a copy of which he kept bedside during his 120-day submersion. 

Speaking to an AFP journalist halfway through his stay, Koch said he and his team wanted to prove that “the seas are actually a viable environment for human expansion”, and they wanted to rethink where humans could live permanently.

“You can’t be claustrophobic,” he said, and “projects, good wine and good whisky” are the secret to survival.

Thumb image credit: Astronautas Tropicales / Shutterstock.com