When a six-time World champion offers you some advice, you really should listen.Neil Rutter has not only been crowned World Bog Snorkelling champion six times, but he is also the world record holder. And yet the nugget of knowledge from his vast experience of traversing 120 yards (110 metres) via two 60-yard lengths in a trench – dug 4ft deep and 3ft wide in a Welsh field – filled with murky, mucky river water is not a tip about technique.“Try not to swallow the water,” he tells The Athletic.No one plans to swallow the bog water, but in this brilliantly eccentric and crazy annual tradition in Waen Rhydd bog, outside the small town of Llanwrtyd Wells in Mid Wales, it is a risk the hundreds who don weird and wacky costumes to descend into the twin trenches and dive into their dark waters are willing to take.According to folklore, as with many of the United Kingdom’s more bizarre sports and pastimes, the idea to jump into the bog and snorkel was conceived after a few ales in a local pub. But, as mad as the idea may have seemed back then, the tradition is still going strong 40 years later with participants coming from around the world to cast their dignity aside — along with a warm robe — and take the plunge into the freezing water.Over 200 competitors come to Llanwrtyd Wells each year to swim in the muddy water (Harry Engels/Getty Images)Bog snorkelling was the brainchild of some locals who wanted to attract more people to the area after the success of the town’s other sporting showpiece, the Man versus Horse Marathon, which began in 1980 and features runners racing against mounted horses over 22 miles of rugged terrain, including bogs, ditches and steep hills. That annual challenge was conceived after an argument in a pub over whether a man or a horse would win such a face-off over the unforgiving Welsh terrain. Bog snorkelling came about in a similar way.“They were brainstorming in the pub and they didn’t want to do another running event,” explains Bob Greenough, one of the volunteers who organise the annual world championships. “They thought about swimming but the local river is either too shallow or running so fast you would soon find yourself in the sea.“Someone said, ‘Well, I’ve got a bog in my back garden’. They went away and, the next day, they miraculously remembered what they had been talking about, so they looked at the bog. They realised they couldn’t swim properly in it so they came up with the idea of snorkelling it.”World Bog Snorkelling ChampionshipsRob TannerThe rules are that no recognised swimming stroke can be used. There is very little use of the arms, so the propulsion down the trench should come from the legs.Rutter, a 42-year-old teacher from Bath, first competed in 2017 and, as well as his six victories, he has broken the record twice. He has entered bog snorkelling retirement now but his record of 1:12.34, set in 2023, looks likely to last some time.