Many have heard that La Ruta de los Conquistadores is the hardest mountain bike race in the world. (Don't take our word for it. Lance Armstrong, who knows a thing or two about competing against the best of the best in the most treacherous conditions, said this was the hardest thing he's ever done on a mountain bike.)

But what is it about the race, founded in 1993 by Mountain Bike Hall of Famer Román Urbina, that is so legendarily difficult? Why, for nearly three decades, has it brought cyclists from all corners of the globe — from as far away as Australia, New Zealand, Europe, and Saudi Arabia — and all walks of life to Costa Rica?

Here's a primer on what makes La Ruta so damn hard and, at the same time, so stunningly epic. 

225 Kilometers, 5 Mountain Ranges, 3 Grueling Days, 1 Continent

La Ruta is a three-day, cross-continental race from one end of Costa Rica to the other, starting on the Pacific Ocean side of the country and ending in the Caribbean Sea. Over the course of those three days, riders have to contend with five mountain ranges, the top of a volcano, 225 kilometers, 8,000 meters of elevation gain, and 20 unique microclimates. (It might be freezing cold in the morning and then, almost before you know it, it will be extremely hot, and you're sweating profusely.)

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The terrain, too, is ever-changing, from flat ground to uphill climbs that seem almost impossible. Racers have to overcome technical sections, rainforest conditions, and loads of mud, dirt, and ash. One part of the race, when you have to cross Carara, is especially grueling. Known as "La temible Carara," translated in English to "The Fearsome Carara," the area spans 14 to 15 kilometers, and usually takes racers anywhere from 100 minutes to three hours to cross. Racers have to carry their bikes and run much of this section on foot. (Only horses and racers can enter this excessively challenging portion of the course.)

Along the way, racers can expect to come into contact with everything from oxen to dogs to horses to farm vehicles (not to mention some fast-moving traffic when on roads).

"It's a personal growth journey," said Urbina, who designed the route based on the Spaniards' expedition to Costa Rica in the 1600s. "You fight against your own demons with a lot of people next to you, but it's your own race. It is nobody else's. It's a real adventure and anything can happen, so you've gotta be prepared. You've gotta be careful. You've gotta depend on yourself and your abilities."

'La Ruta Literally Changed My Life'

La Ruta, an original documentary about the race, chronicles the journeys of four competitors during the 2019 race: Josep Betalú Constantino, a professional mountain biker who had won La Ruta in back-to-back years entering 2019; José Santos Miranda Blandon, another pro mountain biker and banana farmer who had been doing the race for 17 years; Amy Palmiero-Winters, a below-knee amputee whose left leg was amputated following a motorcycle accident; and Carlos Luis Carmona Aguilar, who was blinded 31 years ago and was attempting to complete La Ruta with a tandem guide.

"La Ruta literally changed my life," said Palmiero-Winters, who in 2021 set the Guinness World Record for fastest 100 miles on a treadmill by a below-knee amputee. (She did it in 21:43:29.) "I've always thought that I've done different things that have dropped me, basically, to my lowest point. But today took me to a whole new level of who I am, what I'm capable of, and basically what I want to do with my life."

And when you complete it, as is the case with all extraordinarily daunting things, you come out the other side a different person.

"La Ruta is beyond," one racer said. "Beyond where you thought you could go, beyond who you thought you were, beyond places you thought you'd ever be able to see."

Watch the documentary in its entirety above, complete with incredible footage and highlights of some of the most epic moments of the three-day expedition.