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1. Iditarod Trail Sled Dog Race - Anchorage to Nome, Alaska

"The Last Great Race on Earth," the Iditarod Trail started out as a supply route. In 1925, when diphtheria broke out in Nome, 20 mushers and 150 dogs rushed to deliver the antiserum from Anchorage. Every year since 1973, mushers from all over the world and their teams of 12-16 dogs prepare for 1,150 miles of snowy tundra, impenetrable forest and rocky terrain. If that's not enticing enough, this year's event starts March 3rd, when the temperatures are below freezing and daylight hours are still minimal.

2. Hell's Gate - Il Ciocco, Tuscany, Italy.

Tucked away in the picturesque mountains of Tuscany is one of the world's most difficult Enduro races known as Hell's Gate. The race was designed in 2006 by the legendary Fabio Fasola who intended to separate the good Enduro racers from the amazing. Hell's Gate continues to serve its purpose every year, and in 2010 alone, just two of the 103 participants were able to complete the course.

3. Ice Climbing World Cup - Kirov, Russia.

Rock climbing might be a popular sport for some, but throw in some ice and it's an entirely different game. Racing up a sheer ice wall with nothing but two ice picks in your hands and the spikes on your shoes might seem inconceivable to most, but to the participants of the 2012 Ice Climbing World Cup, it's just another competition. The best ice climbers are nothing short of acrobats as they manoeuvre their way up and down the ice with serious agility, strength and guts. The final event in the World Cup series, Kirov promises to showcase the year's finest talent and the fastest competitors.

4. Crashed Ice World Championship - Quebec City, Canada.

One of the most exciting up-and-coming winter events, this extreme sport generally consists of burly ice hockey players strapping on their skates and racing down an urban ice track. Sound easy? Add some sharp turns, steep drops, jumps and nasty falls and you've got nothing short of mayhem. The final leg of the 2012 World Championship Tour ends in Quebec City, at the Fairmont Le Chateau Frontenac. Last year, more than 100,000 spectators filled the night streets of Rue des Carrieres, and this year it's expected to be even bigger.

5. Billabong Rio Pro - Rio de Janeiro, Brazil.

Screeching down the side of a massive wave with nothing but a board to save you from the roaring ocean is something only a professional adrenaline junkie could handle. The Association of Surfing Professionals Tour circles the globe every year, throwing its best at Mother Nature's toughest waves from the Gold Coast of Australia to the Banzai Pipeline of Hawaii. This year, the stakes are even higher with a $500,000 payout to the winner of the Billabong Rio Pro in Brazil.

6. 24 Hours of Le Mans - Le Mans, France.

This year's event marks the 80th anniversary and will be held on June 16th and 17th. The trick to Le Mans isn't simply speed; it's juggling the mechanical needs of the car, especially the tires and brakes that run down quickly, while testing the stamina of the three-man driving team. The cars take off at 4 p.m. and fans fill the stadium and engines scream along the track until 4 p.m. the following day. Some 200,000 visitors are expected to attend the parade held the Friday night before the race, a particular fan favorite.

7. Race Across America - Oceanside, Ca to Annapolis, Maryland

More than one-third longer than the Tour de France and crammed into a smaller timeframe, the Race Across America covers 3,000 miles of land. The race is open to amateurs and professionals, young cyclists and old cyclists and individuals or teams - as long as they complete the event in less than nine days. For those who race as individuals, they are expected to ride upwards of 350 miles a day to maintain an adequate pace, while teams can be as large as eight members.

8. The X Games - Los Angeles, California, United States.

If you missed this year's Winter X Games Event in Colorado (and Shaun White's perfect score in the SuperPipe), have no fear because you can still catch the Summer X Games in Los Angeles. The X Games have expanded so much in recent years that there are even events held in China and France. This year's summer events are sure to include competitions in motocross, rally car, BMX and skateboarding. And true to form, new tricks will be tested and a nasty wipeout or two is almost a guarantee.

9. Badwater Ultramarathon - Badwater Basin to Mt. Whitney, Ca.

Beginning at Death Valley's Badwater Basin 280 feet below sea level and ending, 135 miles later, at the base of Mount Whitney (elevation 8,300 feet plus), the Badwater Ultramarathon is considered one of the most difficult foot races in the world. Mid-summer Death Valley temperatures can reach 130 degrees Fahrenheit, but there's a big payout, right? Think again. For participants who have adequate finishing times - say under 60 hours - they receive a commemorative medal and bragging rights to completing the world's most difficult race.

10. Artistic Wingsuit Competition in Siofolk, Hungary.

It's not a bird and it's not a plane - it's a wingsuit flyer. For those who decided skydiving was no longer a thrill, wingsuit flying was introduced and is quickly becoming a sought-after extreme sport thanks to action flicks like Transformers: Dark Side of the Moon. Daredevils interested in taking up such a sport jump out of planes thousands of feet in the air and take flight over several miles of the earth before popping open their parachute and landing (safely we hope). And like any sport, there is of course an art to the form and style of wingsuit flying, which can be witnessed during the two back-to-back competitions - the International Artistic Wingsuit Competition and Marko Mike's Wingsuit Boogie.

(Editing by Paul Casciato)

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