Competitors must wear snorkels and flippers, and complete the course without using any conventional swimming strokes. Wet suits are not compulsory, but are usually worn.
The mud at Peatlands Park in Dungannon, was in perfect condition yesterday as dozens of brave souls took to the water.
The competition was founded by park warden Colin Gates as a fun way to raise awareness about bog lands and their unique beauty and biodiversity.
It coincides with International Bog Day in Dungannon and attempts to highlight the threat to peat bogs — 96% of which have been destroyed since 1945.
The World Bog Snorkelling Championship, first held in 1985, takes place each August Bank Holiday in Llanwrtyd Wells in mid-Wales.
Northern Ireland’s Conor Murphy is the current men's World Champion with a record time of 1:25.87 seconds.
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