America’s historic highways occupy a strange place in the modern road network. They’re preserved, celebrated, photographed, and driven by millions of travelers a year, and yet many of them were engineered for a world of 40-mile-per-hour cars, no seat belts, and a fraction of today’s traffic. The result is a category of road that is simultaneously a tourist attraction and a genuine safety problem: beloved corridors where nostalgia and risk share the same pavement.
Route 66 is the defining example. The Mother Road turns 100 this year, and its corridor, a shifting braid of preserved alignments, frontage roads, and the modern interstates that replaced it, still carries enormous traffic across eight states. It also still carries a body count. According to this study of Route 66’s deadliest stretches, the Route 66 corridor recorded 1,240 fatal crashes in the four years from 2021 to 2024, with the worst concentrations clustered on rural segments in New Mexico, Missouri, California, and Arizona.
To understand how a century-old highway ends up on a modern danger map, it helps to understand what these roads were and what happened to them.
Built for a Different Era
When Route 66 was commissioned in 1926, it wasn’t designed the way we design highways now. It was stitched together from existing roads, farm routes, main streets, and wagon paths into a continuous line from Chicago to Santa Monica. Much of it was a narrow two-lane ribbon, and its geometry followed the land rather than cutting through it: around cliffs, down river grades, through the middle of every town along the way.
Some of that geometry was lethal from the start. Just past Owl Rock near Mesita, New Mexico, early drivers had to swing a blind curve around a massive sandstone cliff that completely hid oncoming traffic, a spot that earned the name “Dead Man’s Curve” by the early 1930s. Illinois had its own Dead Man’s Curve in Towanda, a sudden 90-degree turn that caught drivers off guard for decades. In Devil’s Elbow, Missouri, the road twisted down steep river bluffs through blind turns and winter ice. Rising traffic and cars without modern safety features did the rest; within its early decades, the highway had earned the nickname “Bloody 66.”
The Bypass Era Solved One Problem and Created Another
The interstate system gradually replaced Route 66; it was formally decommissioned on June 27, 1985, and by most measures, the new roads were dramatically safer: divided lanes, engineered curves, controlled access. Notorious hazards like Devil’s Elbow were bypassed or blasted through by engineering projects.
But the old road didn’t disappear. It became a corridor: in some stretches, the historic alignment and the modern interstate occupy the same roadway; in others, old 66 survives as a separate parallel road; in others still, the two weave together and apart. That layered geography is precisely where the modern risk lives. Today’s deadliest stretches sit where high-speed interstate traffic, slower local traffic, and sightseeing tourist traffic all share or intersect the same corridor, often with drivers who are unfamiliar with the road, distracted by the scenery, or moving at radically different speeds.
The numbers bear this out. Of the eight deadliest rural stretches identified along the corridor, New Mexico, the state with the largest share of the route, accounts for four, including a 21-mile section west of Albuquerque near the old Dead Man’s Curve alignment that recorded 18 fatal crashes and 25 deaths in just four years. Missouri’s worst stretch sits immediately west of Springfield, the very city where the “66” designation was born in 1926. History and hazard, in these places, literally overlap.
Geography Never Stopped Mattering
Some historic-highway dangers were never really about the era at all; they’re about the land, and they’ve outlasted every improvement. California’s Cajon Pass is the clearest case: the gap between the San Bernardino and San Gabriel mountains funnels desert wind into gusts that have been flipping high-profile vehicles since the highway era began, and the steep southbound descent that once cooked the brakes of Model A’s still makes modern drivers white-knuckle the wheel. The 17-mile Cajon corridor recorded 16 fatal crashes and 18 fatalities over the study period, and officials still monitor wind speeds there to issue warnings and restrictions.
Arizona offers the opposite lesson. West of Winslow, the terrain is so flat and the road so straight that the danger is psychological rather than physical: high speeds plus hypnotic monotony equals drivers caught completely off guard when something goes wrong. Twelve fatal crashes in 17 miles of “easy” road.
Staying Safe on the Historic Stretches
None of this is an argument against historic highways, quite the opposite. These roads are worth preserving, and the centennial will rightly send more travelers down them than at any point in decades. But preservation and safety have to be held together, and mostly that falls to the driver. A few habits go a long way on corridors like this one:
Treat old alignments like what they are. Historic two-lane sections were built for slower travel and slower cars. Match your speed to the road’s actual design, not the posted interstate limit nearby.
Expect mixed traffic at mixed speeds. Wherever old roads and new interstates run parallel or cross, you’ll find local traffic, long-haul trucking, and sightseeing tourists sharing space at very different paces. Give extra following distance and expect the unexpected merge or sudden slowdown.
Take posted geography warnings seriously. Wind advisories through mountain passes like the Cajon exist because vehicles really do get pushed around up there, high-profile vehicles especially. Don’t treat them as boilerplate.
Stay engaged on the “easy” stretches. The flattest, straightest miles are consistently where drivers zone out, and where a moment of inattention has the least room for error. Ironically, these are the stretches that demand the most deliberate focus, not the least.
Plan around dusk if you can. Fading light, fatigue, and rising traffic all converge in the early evening on long road trips. If a day’s drive can wrap up before dark, that’s a meaningful edge.
A hundred years on, Route 66’s dual legacy endures, both as the most romanticized drive in America and a corridor that still demands genuine respect. The travelers who understand both halves of that legacy are the ones who get the whole experience, neon, nostalgia, and a safe arrival at the end of it.