THOUSANDS waded through water, ice, electricity and of course mud in the first day of Tough Mudder on the Sunshine Coast.
More are lining up again today - either to prove it to themselves, to others, or to just have a laugh with mates.
The Sunshine Coast Daily has shot and edited a couple of videos to show just what competitors from Saturday had to go through.
This is the biggest event in Tough Mudder's history according to creator Will Dean. More than 23,000 were expected to take on the 20km course over the two days.
Tough Mudder Australasia managing director Drew Ward said the event, held in Caloundra, will be the biggest course globally this year.
"Participants will be challenged by a gauntlet of obstacles at the Sunshine Coast event."
The Sunshine Coast Tough Mudder course will include 18 obstacles spread out over 20km of cross-country track.
Some highlights will include obstacle "Arctic Enema", which is a swim through icy cold water, and "Trench Warfare", where participants will crawl through narrow, dark, muddy trenches.
Mr Ward said the toughest obstacle would depend on the individual mental and physical preferences of participants.