So you like mountain biking, you've done a couple of races and think you're a bit of a pro, right? If you're really looking to push yourself to the limit, you've come to the right place.
Picture yourself pedalling for hundreds of miles through snow, sand, mud and water, encountering venomous snakes and battling for 12-hours a day through arctic conditions or sweltering desert heat.
"It's all about pushing yourself to battle for 12-hours a day through arctic conditions or sweltering desert heat"
This is all part of what it's like to tackle hardest mountain bike races on the planet. We're not talking about elite events here like the Tour de France or the Downhill World Cup.
Instead, we've focused on the toughest endurance mountain bike races around - that you can sign up for right now.
[part title="Yukon Arctic Ultra, Canada"]
Catch a plane to the depths of Canada's Yukon in February and take part in arguably the world's toughest ultra-marathon.
You can choose to race either a marathon, 100 miles, 300 miles or a mind-blowing 430 miles across the frozen arctic tundras and braving temperatures of -50°c using pedal power alone.
Alternatively, some people take on the challenge by foot or on cross-country skis. If you book now for next year, the longest race will only cost you €2,300!
Click here to find out more about getting involved.
[part title="Cape Epic, South Africa"]
In 2002, a South African guy Kevin Vermaak took part in the famous La Ruta race in Costa Rica and was inspired to start something similar in his home country.
Now, 12 years later, the race known as Cape Epic invites hundreds riders to cycle 435 miles over eight days including 14,850m of climbing through South Africa's wine regions.
Amateurs compete alongside professionals, but you'll have to get in there early as spaces are limited. You can either apply through the early bird option or hope to be allocated a lottery space.
It's a team event, so you'll need someone mad enough to do it with you. Entry fees for 2015 are R 53,700 per team (£2,971). Read more about the race here.
[part title="Simpson Desert Bike Challenge, Australia"]
If normal ultra-cycling races weren't enough for you, why not take it to the desert?
The 360 mile Simpson Desert Bike Challenge is reserved only for the toughest of riders. It's five days of gruelling biking through the blistering Australian heat.
You'll pass over 700 sand dunes, sprawling salt lakes and gibber rock plains before reaching the final destination at Birdsville, Queensland.
Just to make matters harder, there is a minimum average speed of 12kph with a sweep following behind that picks up the stragglers whether they like it or not!
Fancy entering? Click here to learn more.
[part title="Salzkammergut Trophy, Austria"]
As far as organisation goes, the Salzkammergut Trophy is regarded as one of the best.
With over 4,000 participants taking part, only the hardiest take part in the Extreme Course, a 211km stretch over an altitude of 7,049m that takes you all over the alpine region of Salzkammergut.
It's a UNESCO Heritage Site, so expect spectacular mountain top views over lakeside villages along the way. Once you've completed all, you can treat yourself to a well-deserved ice cold pint of Stiegl!
It's also one of the cheaper events in enter - just €85 if you book now. Check out more about it here.
[part title="La Ruta de Los Conquistadores, Costa Rica"]
La Ruta is famous worldwide for being one of the most epic rides in the world. It's not the longest - only 161 miles - but it traverses the whole of Costa Rica from the west Pacific coast to the east coast on the Caribbean over an altitude of over 6,300m.
It originally came about after an adventurer called Roman Urbina decided to follow the steps of the Spanish Conquerors on his mountain bike for fun. He decided it would make a cool international event - and so La Ruta was born.
Think snakes blocking the singletracks, gnarly crevices, rocky terrain through the jungle and a total disregard for health and safety. As with many of these races, if you don't make the check points within 12 hour time slot, you'll be carted to the finish line. Better get training then!
Find out more information here.
[part title="Yak Attack, Nepal"]
Yak Attack is the highest mountain bike race in the world, covering over 400km and altitudes of 12,000m. If you're not super fit, don't even bother considering it.
The weather flips between humid jungle territory at 30°c below dipping well below -15°c as you climb further up the mountain. Along with that you'll get everything from muddy bogs to wade through, seriously steep singletracks, rickety suspensions bridges and snow!
At 5,416m above sea level, the oxygen levels are 50 per cent less than below, so there's more to overcome than just treacherous trails.
It costs £2,295 per person. Get yourself better acquainted with the event here.