What can be tougher or more grueling than Hawaii's Ironman Triathlon or the Badwater Ultramarathon? How about Tough Mudder, a 12-mile obstacle course that drags contestants through mud, fire and even 10,000 volts of electric current.

Started in 2009 by Will Dean, a former British counter-terrorism agent as a way to bring some fun and variety for athletes bored of mundane marathons and triathlons, it has today become a popular challenge, that is held in many parts of the world including, Europe, USA, Canada, Japan and even, South Africa.

The obstacles are so tough that one in five contestants drop out along the way - Those that do get through it, take about 4 hours to complete the course - About the same time it takes an average marathon runner to run 26.2 miles. For those looking for an additional challenge, there is the World's Toughest Mudder, a 24 hour-challenge that takes place annually in November - However, entry to this is reserved for qualified contestants only.

The most recent Tough Mudder challenge took place on the grounds of Scotland's historic Drumlanrig Castle and Country Estate in Dumfriesshire, on July 14th, 2012. The inaugural Scottish event attracted 90,000 athletes who paid about $150USD each, to participate in the challenge that entailed overcoming 30 obstacles.

The hurdles included wading across a mile-long muddy ditch, jumping into an ice filled area, running in thick smoke created by blazing, kerosene-soaked straw with flames as high as 4-feet tall. If that was not enough there was the electric fence the contestants had to go under - A slight miss and a 10,000 volts jolt would happily zap through their bodies.

Whether this is the World's toughest athletic event or not, really depends on each individual athlete's perception of what tough really means - Running a 135 miles ultramarathon is not for the faint of heart either. However, according to the organizers, Tough Rudder is more challenging because it tests contestants various different ways - Toughness, strength, stamina, as well as, mental grit.

But the biggest advantage Tough Mudder has over all the other challenges is that it is a fun event - One where contestants are not trying to outdo each other because, there are no major prizes to be won at this challenge - Just a cold glass of beer or root beer and a group of cheering friends that help get you through this grueling event. So do you think this is the world's toughest athletic challenge? Be sure to let us know by adding your comments below.

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