Competitors in the World Bog Snorkelling championship come armed with mask, snorkel and, presumably, a sense of humour. The August bank holiday shindig, in Llanwrtyd Wells, the smallest town in the UK, has events for men, women and for both sexes - in fancy dress. The contest involves squelching through a 60-metre peat bog as fast as possible.
Further afield, in Boryeong, South Korea, millions of mud fans descend on the annual Mud Festival in July. The minerals in the mud are apparently good for the skin but, really, who cares when you can spend whole days wallowing, sliding and wrestling in mud. And while you're packing your oldest clothes...
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