Picture this: you're face-down in a freezing cold, murky bog in the middle of Wales, trying to swim two lengths of a 60-yard trench filled with stagnant water and decomposed plant matter. Oh, and you can't use conventional swimming strokes. Welcome to the wonderfully absurd world of bog snorkeling, where common sense takes a holiday and participants emerge looking like swamp monsters.

The whole thing started in 1985 when Gordon Green, landlord of the Neuadd Arms pub in Llanwrtyd Wells, Wales, was probably having one too many pints with his mates. This tiny town had already established itself as the home of eccentric events, but Green wanted something truly ridiculous. His solution? Cut a trench through the nearby Waen Rhydd peat bog and challenge people to swim through it wearing snorkels and flippers. The catch that makes it properly mad: competitors must rely solely on flipper power, meaning traditional swimming strokes are banned. You're basically doing an underwater doggy paddle through what looks like chocolate pudding.

What began as a local laugh has somehow evolved into an international phenomenon. The World Bog Snorkeling Championships now attracts hundreds of competitors from across the globe, all eager to thrash their way through the murk. The current world record stands at just over 1 minute 18 seconds, set by Kirsty Johnson in 2018, though times vary wildly depending on conditions. Some competitors take it deadly seriously, training in pools with weighted vests and specializing in flipper techniques. Others show up in elaborate costumes—dinosaurs, superheroes, brides—because if you're going to do something this daft, you might as well commit to the bit.

The sport has spawned variations that are somehow even more bonkers. Mountain bike bog snorkeling requires participants to ride a lead-filled bike along the bottom of the trench, while bog snorkeling triathlon combines running, cycling, and the traditional murky swim. There's even bog snorkeling in Ireland and Australia now, though the Welsh fiercely maintain their championship as the original and best.

Here's the thing that gets me: this started as a joke to bring tourists to a struggling Welsh village, and it actually worked. Llanwrtyd Wells, population roughly 850, now hosts thousands of visitors for bog snorkeling and their other quirky events like the Man versus Horse Marathon. Who knew that the secret to economic development was convincing people to swim through decomposed vegetation? It's testament to humanity's endless appetite for doing ridiculous things just because we can.