Transcript for Dead Man's Curve: US's Most Notorious Highways

well, the labor day holiday is just a week away. We have a staggering number for you tonight. 29 million americans will be traveling in a car for the holiday. But would you drive on these roads if you knew their nicknames in advance? Highway to heaven, blood alley, massacre mountain? Here's john quinones tonight with some of the most dangerous roads in this country. Will you be traveling on any of them as the summer comes to a close? Did you see that? That was a little crazy. Reporter: The locals in these hills know john cossentine as the photographer who makes a living capturing death-defying rides along a legendary stretch of road called "the snake" on mulholand highway in the mountains outside l.A. Here, there's no room more mistake on the snake. Reporter: The snake leads off our list of ten treacherous american roads. It's very seize si to get into trouble up here. We have a lot, accidents every weekend. Yeah, I don't know what happened. It just totally slid. Reporter: Even the most experienced riders can wipe out on the snake. Adey bennet trashed his tibia. I never broke a bone until that day and it happened on the snake. Reporter: Curiously, it's rural roads like these and not the big interstates where those notorious pileups usually occur. Whoa! Reporter: They account for a majority of the 37,000 annual traffic deaths across the country. That's more than gun deaths, industrial accidents and soldiers killed in action, combined. Some of the reasons these scenic roads are lined with crosses? Well, people more often don't wear their seat belts and tend to drive faster. And there are plenty of animals sharing the roads. If a driver has an accident, they are on their own. The road's gallery includes north carolina's scenic highway 129. It has so many twists and turns, it's earned the nickname "tail of the dragon." Route 6 on cape cod became suicide alley for its frighteningly narrow lanes. And it's obvious why this hairpin turn on route 17 near binghamton, new york, is known as kamikaze curve. This is where sheriff david harder has seen more than 300 accidents. Kamikaze curve got its name because as soon as it rains, it's like an ice skating rink. Cars slide right off the road and crash. Reporter: But for sheer body count, it's hard to match the innocently named red narrows, a treacherous stretch of utah's route 6, where the beautiful meets the deadly as cars and trucks traverse through rockslides, ice and switchbacks. It's dangerous, because you're hitting these curves and people are going too fast. And there's a truck or somebody coming the opposite direction. Reporter: Kathy justice says that practically everyone who lives in this small utah community of price has lost a friend or loved one to this road. A staggering 30 people per year. Kathy lost her own mother. I became involved because many of my friends passed away and I attended their funerals. Every time I see it, it's fresh, just like it happened yesterday. Reporter: It took kathy's friend jeanette sorensen ten years to muster the courage to drive down the same route 6, the road her son dusty died on when he was just 18 years old. I just wonder what he would have grown up and been, if he would've been married and had children. He just was so young. He missed out on his whole life. Reporter: Now most of us will never drive down these little, lethal thoroughfares. But don't think everything's honky-dory on the major interstates millions use every day. They have major problems of their own. dan McNichols is passionate about how america's crumbling roads have become death traps from coast to coast. He's devoted himself to restoring this 1951 hudson for a cross country ride, a look at the underbelly of america's deteriorating road network. What's the common denominator in all of america's deadliest roads? All the things that you don't see. You don't see breakdown lanes. You don't see lit tunnels. You don't see good signage. You don't see divided highways. Reporter: Exhibit a -- new york city's cross bronx expressway that touches the tip of manhattan. 175,000 people use it every day and there are an average of 777 accidents here every year. It's a treacherous, tortured mess. When you have an old highway that is trying to behave like a modern highway, you're in trouble. That's exactly the problem of the cross bronx expressway. It is jammed into rock. It's below grade. It's in a crowded area. Reporter: And that we could never fix? We could, but it would be just too disruptive. Reporter: Adding to the danger -- you get tunnel blindness when you first drive into a tunnel. And what they try to do is hit you with a lot of light in modern tunnels. But you can see it's barely lit at all. Reporter: Come out of the tunnel only to find an obstacle course through the potholes. But in the immediate moment that you strike something like a deep pothole, you have an adrenaline rush, you lose your focus. You might swerve into another lane. Reporter: There are other crowded deadly interstates in the McNicoll hall of shame. Perhaps you survived one of these today. The highway of death, u.S.24 near toledo, ohio, notorious for gruesome, head-on collisions. The beeline expressway in florida with its lethal lack of guardrails. And the highway to heaven, around cincinnati, with its he hellish hills and poor visibility. Even roads that look safe like highway 15 from las vegas, can be a roll of the dice. I call it crap shoot alley. What's dangerous is what you would think it would be safe. It's flat and straight. People either overcome by highway hypnosis, they fall asleep or they pick up their speed and they drive too fast. Reporter: Now, the good news. Some of the most dangerous roads are being made safer. And road deaths have been on the decline. Partly because of people like kathy justice, who lobbied her state harod to get roads fixed. Is it going to be costly? Yes. Is it going to be necessary? Yes.

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