Teams of 2 not only compete against others, but constantly assist each other.

Early on the field was fairly tight together, but that didn't last very long.

Two female teams finish one of the swim sections on one of many tricky exits.

Swedes Rasmus Enlund and Fredrik Haglund of Team Actic tackle a technical trail on the way to 6th place.

If it was easy, everyone would do it. Here Brits Mark Threlfall and Jack Grundy of Team T3 Triathlon get ready for another swim.

Female Team SurfSpot with Annika Ericsson and Maya Tesch stormed to a win despite only meeting each other a few days before the race.

Male Swedish counterparts Henrik Wahlberg and Klas Wiréhn of Team SurfSpot managed to reach the finish in just under 10 hours.

A slight hesitation before the next swim segment for this mixed team. This Spanish - German team did not finish the race.

Petter Askegren aka Petter and Jessica Thorelius of Team Addnature keeping his eyes on the trail.

Paul Krochak helps his teammate Björn Englund out of the water on the way to the win.

Another Swedish team of Marcus Hultgren and Helena Sivertsson battled hard but had to settle for the runner-up spot. The team behind them is an all-male team.

Scrambling along the edge of one of the many islands featured in this super tough race.

Yes, you swim with your running shoes and run with your wetsuit in a race with so many transitions.

The scenery around this Stockholm archipelago is stunning, but windy conditions made it extremely difficult.

Defending champions Lennart Moberg and Daniel Hansson of Swedish Armed Forces were on the hunt all day, but in the end fell a little short.

Strong swimmers Simon Börjeson and Rasmus Regnstrand of Team Addnature Östersjösimmet held the lead for a long time but fell back to fourth place.

Windy conditions made some of the swims extra hard, especially late in the race.

Fighting the water and fatigue during one of the shorter sections.

The new SwimRun world champions.