Courtesy of WOWSA, Huntington Beach, California.

Night and day. The differences between the Olympic 10K Marathon Swim course and conditions at the 2012 London Olympic Games and the 2016 Rio Olympic Games are significant.

Photos from the men’s 10 km course in London’s Serpentine are compared against the video from the women’s 10 km course on Copacabana Beach at the 2007 Pan American Games in Rio de Janeiro, Brazil.

Night and day. Calm and turbulent. Open water versus rough water. An interesting study in contrast.

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