Strel swam the Amazon River, commencing on 1 February 2007, finishing 66 days later on 7 April 2007. This was a record-breaking distance of 5,268 km (3,273 mi), longer than the width of the Atlantic Ocean. He had escort boats that were prepared to pour blood into the river to distract meat-eating fish such as piranhas.

Yes, the Slovenian marathon swimmer Martin Strel became the first and only person officially recognized for swimming the entire length of the Amazon River. In 2007, Strel completed the Herculean task by swimming 5,268 kilometers (3,273 miles) from the headwaters in Peru to the Atlantic coast of Brazil. The journey took him 66 days, during which he faced extreme heat, piranhas, crocodiles, bull sharks, and the legendary "candiru" parasite. Strel reportedly swam up to 10 hours a day and relied on a "high-calorie" diet (and a moderate amount of wine) to sustain his energy. His swim was documented in the film Big River Man. While other explorers have rowed, kayaked, or walked the length of the Amazon, Strel’s feat remains a unique testament to human endurance and physical power. In 2026, no one else has successfully repeated the full swim, as the environmental and security risks of the Amazon basin have become even more complex, cementing Strel's place in the Guinness World Records as the undisputed king of long-distance river swimming.