Strel's first two river swims were in the Krka River (105 km) in Slovenia in 28 hours in 1992, and in the Kolpa river (62 kilometres (39 mi)) in 16 hours in 1993. In 2000, he swam in the Danube River (2,860 kilometres (1,780 mi)) and achieved the world stage swim record (3,004 kilometres (1,867 mi) in a 58-day swim. In July 2001, he set another more world record — 504.5 kilometres (313.5 mi) when he swam non-stop in the Danube River for 84 hours and 10 minutes.
In 2002, he swam along the entire Mississippi River (3,885 kilometres (2,414 mi)) in 68 days. In 2003, he swam the Argentine Paraná River (3,998 kilometres (2,484 mi)). On 10 June 2004, Martin started swimming down the Yangtze River (4,003 kilometres (2,487 mi), the longest river in Asia and the third longest in the world) in China. He reached Shanghai in 40 days on 30 July 2004, one day earlier than planned.
Strel swam the Amazon River starting on 1 February 2007 and finished 66 days later on April 7, 2007. This was a record-breaking stage swim of 5,268 kilometres (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.
In 2007, the Nile had been proposed as his next river, but Strel said, "I am not going to do the Nile. It's long but not challenging enough, it is just a small creek. The Amazon is much more mighty."
In June 2011 Strel completed his Colorado River Swim challenge for a new TV show. He will appear on the History Channel and the National Geographic Channel in the United States in the summer of 2012.
Big River Man
Strel was recently the subject and star of a feature documentary entitled Big River Man directed by the acclaimed art-house director John Maringouin. The film, which won a Best Cinematography prize at the 2009 Sundance Film Festival, was critically praised for its extraordinary blend of comedy and drama. The film chronicled Strel's 3,300 mile historic swim of the Amazon.