Why Pikes Peak is the most dangerous racetrack in America

• In the Rocky Mountains on a century-old public highway sits the most dangerous racetrack in America.
• The 12.7-mile course wraps around the legendary Pikes Peak and ends at the mountain's 14,115-foot-tall summit.
• But even with its deadly hazards, which include 156 blind turns and steep cliffs with no guardrails, drivers continue coming back for the annual Pikes Peak Hill Climb race.
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Following is a transcript of the video.

Narrator: You're looking at the most dangerous racetrack in America. Over 12 miles long, this course climbs through the Rocky Mountains up to the summit of Colorado's legendary Pikes Peak, 14,115 feet above sea level. What starts as a simple road course on a public highway that any ol' person can drive on turns into a dangerous trek above the clouds for the final leg to the finish line. On a mountaintop road with an average speed limit of 25 mph, competitors tear down the track at 140 mph with no braking markers, turn indicators, or frame of reference for where they even are. Just sky in front of them and 2,000-foot drop-offs mere feet to their right. One wrong move and they could easily go over the edge. It's this top section of the course that makes the historic Pikes Peak Hill Climb so dangerous.

The first Pikes Peak Hill Climb was held in 1916, promoted by famous entrepreneur Spencer Penrose. Since then, the hill climb has evolved from a local stock-car race into an international competition featuring some of the most incredible race cars and superbikes ever built. Drivers and motorcyclists compete one by one for the best possible time to the top of the gigantic mountain, and a highway that takes the average person one to three hours to drive gets covered by these professionals in about 10 minutes. And Pikes Peak hasn't gone without seeing its fair share of tragedy. The race's organizers suspended the climb's motorcycle division for 2020 following the 2019 death of four-time winner Carlin Dunne in a crash near the finish line.

But what makes the final few miles of the course one of the most death-defying challenges around can be summarized by four things: the amount of unbound blind turns, unstable road conditions, enormous altitude, and unpredictable environment.

Tommy Boileau: For me, I think the most difficult part of the road was the entire top section. You're well above tree line at that point, so it's just really intimidating visually because there's just barren cliffs everywhere you look.

Narrator: That's Tommy Boileau, a professional racecar driver who competed in his first Pikes Peak Hill Climb in 2019, when he was awarded the race's rookie of the year prize. We spoke with him as well as IndyCar driver and Pikes Peak veteran JR Hildebrand about just what makes driving on top of this mountain so dangerous.

To start with, there's the absurd amount of blind corners. 156, to be exact, throughout the entire Pikes Peak racecourse. But the most terrifying ones can be found at the top.

Tommy: It is incredibly dangerous. There's no guardrails. And at the majority of the corners, the speeds are incredibly high

Narrator: Unlike on a typical track, the majority of Pikes Peak's turns lack any barricades. One mistake at a hairpin bend can send you hurling over the edge thousands of feet, like driver Jeremy Foley in 2012 when his car lost grip of the road. While his car was virtually destroyed in the wreck, miraculously, Foley and his copilot, Yuri Kouznetsov, both walked away from one of the race's worst crashes in recent history.

JR Hildebrand: You know, there are other forms of motorsport that have maybe trees off the side of a stage rally or a water hazard. Even driving at the Indianapolis Motor Speedway, where I might hit the wall going 200 mph. But this is very much in your face. Only one thing's gonna happen if you go off track, and it's not good.

Tommy: You have to learn the road. You have to memorize all 156 corners. There's some corners that look very very similar. Sometimes you're coming into a corner in top of fourth gear and gotta carry 120 mph on exit, but there's another corner that looks almost identical, but you have to slow down to a first gear hairpin on exit.

JR: Just memorizing the circuit and being familiar with it is one of the most difficult things to do. And it's as difficult to do there as it is anywhere in the world. Coming from a road-racing background, you don't have any of those markers, sightlines that you're used to, braking points. There's nothing telling you what's coming up or how close you are to the next corner.

Narrator: Then there's the change in altitude. Pikes Peak stands at a height of 14,115 feet; that's equivalent to the length of almost 39 football fields. For anyone whose body isn't acclimated to the elevation, altitudes this high have very noticeable effects on the human body because of the intense decrease in oxygen levels. These effects can range from simply poor athletic performance to dizziness and dehydration. But for motorsport athletes, even the vehicle can be affected that high up.

JR: You are combatting this element of altitude. So not only is the car working different at the top than it does at the bottom (it's not making as much horsepower, the tires are kind of smoked from this whole run up the hill, the aerodynamics aren't working as well because the air's less dense), but also physically you're experiencing this dramatic change in altitude over the course of the event. I mean, you're ending at 14,000 feet, which feels like you've had a couple beers when you get to the top from being so high up.

Tommy: I am kind of fortunate, being local here. I grew up in Colorado, so I'm used to the elevation. So my blood oxygen saturation is much higher than most other drivers. But you've got a lot of drivers that come in from different countries and states. They tend to struggle with the elevation, so that in itself is a risk because your body takes time to adapt. Just to eliminate any excuse or any errors that we could have, I did run an oxygen bottle inside of the car, which is really common. The majority of the guys, especially the front-running guys, we do run oxygen inside of the car directly into our helmets. But even more so, something that a lot of people don't think about is just the temperature change from start line to finish line. The lower the temperature, the less grip you're gonna have.

Narrator: Drivers at the top of Pikes Peak are also in danger of the unpredictable road conditions, which don't compare to what racers find on your average circuit. The highway is regularly hit by rough weather, but it doesn't receive the same treatment that other streets or professional tracks do to ensure safety. The freezing temperatures at the top of the mountain don't help either.

Tommy: The road itself isn't maintained the same way that a proper racetrack would be. There's no street sweepers going out there to make sure that there's no gravel. And being a 14,000-foot mountain, you get a lot of snow and rain running across the road in different places. But also, that high up in the elevation, the road tends to warp a lot through the freeze-thaw process throughout the winter. So even during race week, there would be a bump that would develop in a corner that wasn't there the day before.

Narrator: In some cases, even changes to the road expected to make it more safe don't help at all. In 1998, environmental organization the Sierra Club sued the city of Colorado Springs, alleging that gravel erosion from Pikes Peak Highway caused water pollution. The city was forced to pave the entire dirt and gravel highway - something that would only make the historic race even more dangerous.

Tommy: People think that driving on the gravel is more dangerous, but in reality, the speeds are much lower if you're driving on that dirt surface. And effectively the racetrack itself is wider. So by getting that pavement placed from top to bottom, the speeds got drastically higher throughout the entire course of the run.

JR: As we think about it in motorsports terms, you're pulling more G's through the corners because it's paved, the cars have more grip. You might be in more control doing that, but because you're generating more load, a little mistake can really move you off the track by a lot more.

Narrator: And from the weather to the environment, all bets are off at the top of Pikes Peak, when you're driving through the Rocky Mountain wilderness. This means storms at the top of the mountain that roll in at a moment's notice on race day. And in some extreme situations, unpredicted encounters with wildlife.

JR: I went up to Pikes Peak last year to hang out with Travis Pastrana. And on his run, it started pouring rain. Then he got above that and it was clear again. So he gets back on it and comes through a blind corner, and there were mountain goats all over the road. So he had to jam on the brakes and lost a bunch of time. And so you hear crazy stories like that all across the board from people.

Narrator: But despite so many life-threatening hazards that come with driving a racecourse like Pikes Peak, professional drivers continue returning and the number of entries keeps increasing. It's an eye-opening, once-in-a-lifetime experience for those who partake, even the spectators. The race is incomparable to that of any in the world, and the level of danger can't be found on any other American race course. But with so much history behind the race, the esteem that comes with being crowned king of the mountain, and the adrenaline rush that comes from driving on the edge of certain death, to drivers this competitive and in love with the sport of racing, the rewards far outweigh the risks.