U.S. Highway 550 is the official cartographer’s term for the 70-mile ribbon of asphalt connecting Ouray and Durango — but it goes by several other names, as well.  

San Juan Skyway, for instance, National Forest Scenic Byway. And, if you want to be dramatic, Highway to Hell. 

That’s how the automobile website MSN Autos recently described it, echoing a number of Internet lists. For Popular Mechanics, the highway ranked No. 3 on “10 of America’s Most Dangerous Roads” in 2013. That same year, it was the only highway in the Lower 48 to make USA Today’s list of the “World’s Most Dangerous Roads.” The transportation blog RoadCrazed featured it on a list of “The Most Dangerous Highways in America.” YouTube users can find videos of trucks crossing 550’s center line and barreling down on terrified motorcyclists. 

Still, the best known name for U.S. 550 as it crosses the San Juan Mountains is “Million Dollar Highway” — though nobody seems to agree, exactly, on how that name came to be. 


Perhaps no one knows the Colorado section of U.S. 550 better than historian P. David Smith, who penned “The Road that Silver Built” in 2009 and co-wrote “The Million Dollar Highway” with Marvin Gregory in 1986. 

According to Smith, the esteemed explorer John C. Fremont once described the San Juan Mountains as “the highest, most rugged, most impracticable and inaccessible” in all the Rockies. The mean elevation of the range is a lung-searing 10,000 feet.

 There’s only one reason roads were made to ever cross the savage San Juans: money. 

In the 1986 book, the authors estimate that a billion dollars’ worth of metals has been produced by the mines scattered between Ouray and Silverton. As costly as ore was to extract, it was even more costly to ship. Prospectors needed a dependable road, and that’s why Otto Mears began stitching together various pack trails, stage roads and railroad grades. 

Nancy Shanks, Region 5 Communications Manager for the Colorado Department of Transportation, said the stretch of road between Ironton and Ouray most bedeviled engineers: “As you go north from Ironton, the road drops 2,000 feet in six miles into Uncompahgre Gorge. There were estimates then that it cost a thousand dollars per foot to construct.” 

But money was to be made. Starting in 1883, Mears — an Estonian immigrant who’d become regionally famous by building the Rio Grande Southern and Galloping Goose railroads — began dynamiting a toll road out of the cliffs looming above Ouray. 

There are rumors that Mears spent a million dollars a mile to build his road, which soon became known as the Million Dollar Highway.

But this origin myth is oft disputed. Another theory holds that the highway is buttressed by fill dirt that contains a million dollars in gold ore. Others maintain that the name comes from a phrase used to describe a common reaction to the road’s perilous twists and turns, especially in winter: “You’d have to pay me a million dollars to drive that stretch in the snow.”

While the nickname originally pertained only to the 12 miles south of Ouray, the entire 70-mile stretch to Durango is today considered to be the Million Dollar Highway. The first motorcar climbed the road in 1911. By 1935, said Shanks, the Million Dollar Highway was completely paved and opened for year-round use.


Million Dollar Highway drivers often arrive breathless at their Ouray or Silverton hotels, marveling that a road with scant shoulders and dangerous exposure contains “no guardrails.”

But it does have some guardrails, Shanks notes, “in areas where we have room for them, so long as the road can maintain an adequate lane width.”

Archival photos show that large earthen blocks did indeed serve as guardrails in the road’s early days. The blocks, unfortunately, left snowplow drivers no place to push the 300 inches of snow that annually fall on the San Juans, so CDOT removed them to aid snow clearing. 

The result? Drivers heading south from Ouray are white-knuckled from the road’s relentless turns and squiggles, and jittery passengers gaze out their windows into a near-bottomless void. 


To travel the Million Dollar Highway is to have your head on a swivel. Look this way at a herd of bighorn sheep. Look that way at a 100-foot waterfall. Locals often debate whether the fluorescent greenery of June matches the fiery golden leaves of October. 

The road soars high in the San Juans, summiting three lofty passes: Red Mountain (11,018 feet), Coal Bank (10,640) and Molas (10,970 feet). 

Everywhere are stunning alpine panoramas. At 1.5 million acres, the San Juan National Forest is the largest national forest in Colorado. The hillsides fronting U.S. 550 contain 23 varieties of evergreens. 

Travelers savor the sight of Bear Mountain at the far end of Chattanooga Valley, so named because slide paths and scree fields combine to form an image of a bear seemingly licking a honeycomb held in its paw. 


Red Mountain Pass, per mile, has the highest avalanche hazard of any road on the North American continent. All kinds of slides have terrorized wanderers of U.S. 550, especially in a path called Riverside Slide. In early 1883, two men and 18 pack animals were trying to tramp down the road after a five-foot dump. A slide killed both men and 12 of their 18 burros. 

Around Christmas in 1883, mail carrier Sven Nilsen left Silverton for Ophir. He was never seen alive again. Two and a half years later, Nilsen’s mail sack melted out of a large slide and was spotted by a stage driver. His body was found a little later, and Ophir finally got its mail, only 30 months late. 

In 1963, Rev. Marvin Hudson and daughters Amelia and Pauline were driving to Silverton to conduct a church service when heavy snow halted their progress near Riverside Slide. The family was attempting to install tire chains when a massive avalanche crashed down; its air blast actually threw a snowplow and its driver to safety. The reverend and his daughters weren’t so lucky. Two weeks later, the car, the reverend and Amelia were found 600 feet downhill. Not for two and a half more months did the ice release Pauline. 

According to The Durango Herald, in 2002 “a prisoner in Utah who had been reared in an unhappy succession of foster homes wrote a letter to The Durango Herald hoping to find his birth sister. They’d been separated after his parents died in an automobile accident on Red Mountain Pass when he was 3.”

The deaths finally spurred the construction of a snowshed in 1985 to deflect the perilous avalanches of Riverside Slide. There, you’ll also find a monument to the three snowplow drivers who’ve perished in avalanches while clearing 550: Robert Miller in 1970, Terry Kishbaugh in 1978 and Eddie Imel in 1992. The monument praises “those who have given the supreme sacrifice in the maintenance of Red Mountain Pass. The lonely vigil of the night is known only to these men of courage.” 

A longstanding local rumor had it that the monument grimly contained room for additional names. That’s not actually true. What is true might be even stranger: Country singer C.W. “Convoy” McCall wrote a song about plowing the road. 

“We warned everybody that the slides was runnin’

And 550 was a mess,

But out of the plow shed south of town

Came a blade with a flashing blue light.”


Not all of the Million Dollar Highway’s victims perish.

Among the many reasons to cherish the champagne powder of the San Juans? It saves lives. Shanks described the most dramatic incident as so: “In 2005, six people were coming back from a sporting event when their van veered off the road at Red Mountain Pass. The van rolled more than 400 feet down a 60-degree pitch, but all six survived because they were wearing seatbelts. They later were featured in a commercial for OnStar.” 

According to “The Road That Silver Built,” in 1897, Jack Bell, the mail carrier between Ouray and Red Mountain, was swept off the road and into the canyon. Other horseback riders saw the slide and mounted a rescue, which was abandoned after dark. But Bell remained alive. Air pockets in his snowy prison allowed him to breathe, and he clawed his way out and crawled up to the tollgate at Bear Creek Falls. He’d survived almost 24 hours in the avalanche debris, and was largely uninjured, though he later lost several fingers to frostbite. 

In 1999, a Red Mountain Pass avalanche buried four people — three highway workers and one motorist — alive beneath 40 feet of snow. The avalanche debris that day deposited itself in such a way that air could move throughout the pile. The four victims survived the night, and rescuers tunneled to them the next day.

Multiple accounts support P. David Smith’s assertion that the highway might be safer in winter, because if a car does go off the road, it’s cushioned by snow and comes to a gradual stop due to the white stuff piling up in front of it like snow in a shovel. 

A vacationing couple got swept off the road by an avalanche in 1985; their car came safely to rest 400 feet below. In ’93, according to The Durango Herald, a pick-up truck packed with members of the Fort Lewis College basketball team tumbled 100 feet down a 45-degree slope before a “freak snowbank” miraculously halted them.   


While avalanches dominate CDOT’s U.S. 550 nightmares, the road’s rockslides are just as bad. On Jan. 12, 2014, a quartzite slab the size of a football field and 25 feet thick fractured, engendering an enormous slide that buried a stretch of 550 north of Silverton under 8 feet of rock. 

Unlike avalanche debris, rockfall doesn’t melt. Nor is it easily plowed away. The Million Dollar Highway closed for three weeks, cutting off access to Silverton from the north. 

Silverton Mountain still offered skiing that winter, bolstered by its La Plata County customers. Yet the town was severed from Ouray, Ridgway and Montrose. As The Durango Herald reported, “Silverton’s hotel beds were mostly empty. … Restaurants had only a smattering of diners. Mail delivery required a 440-mile detour. Supplies went undelivered. Residents weren’t able to commute to jobs or see their doctors. Workers were laid off.”

Even more difficult than clearing 550 was protecting it from future slides. For decades, CDOT has erected netting above the road to restrain wayward rocks. The 2014 slide, however, issued from an astonishing height: 900 feet above the tarmac. 

CDOT responded by anchoring 37 netting panels — each one measuring 12-by-72 feet — into the high cliffs. The elaborate system has so far succeeded, Shanks said. “We did have to clear a significant amount of debris from the middle section of that fencing this past spring. And this is likely to become an annual event.” 


U.S. 550’s designation as part of the San Juan Skyway and its continued presence on merry lists such as “21 Drives to Do Before You Die” invites perpetual curiosity. U.S. 550 draws an average of 2,300 vehicles a day, though many more travel the road in summer than in winter, Shanks said. 

All told, the San Juan Skyway Scenic Byway runs 236 miles through southwest Colorado. In addition to the Million Dollar Highway segment, it links Durango to Mancos to Dolores to Telluride and picks up 550 again in Ridgway. The route is especially popular with motorcyclists, who crave its magnificent views and serpentine turns. 

Over time, the Road that Silver Built has become a significant driver of regional tourism, not unlike Telluride Ski Resort, the Durango Silverton Narrow Gauge Railroad or Mesa Verde National Park. 

Long-distance backpackers and mountain-bike tourers traveling the 444-mile Colorado Trail traverse 550 at Molas Pass. There, they detour into Silverton for supplies or invigorate with a dip in icy Little Molas Lake.

Backcountry skiers and snowboarders park their vehicles on 550 near Red Mountain Pass, then tour up to McMillan Peak (12,804 feet), located just east, and Ohio Peak (12,673 feet), just south. Both promise 1,200-foot vertical lines mixed with fun knobs and sub-peaks. 

You’d never know it from the road, but a hotel of sorts sits a mile above Red Mountain Pass. St. Paul Lodge is a funky, rustic structure built in 1974 by Chris George, an esteemed British mountain guide who bought the mining claim at 11,440 feet and organized speed-skiing events in nearby bowls. 

Tourists who trek up the 350-vertical-foot path from the pass to the lodge find a warm, worn place, furnished with antlers, prayer flags, a sauna, old books, and gas lanterns (there’s no electricity). Guests — up to 25 of them — sleep in dorm rooms and eat family-style. 

These days, travelers tend to find the highway more beautiful than deadly. According to Shanks, no avalanches have killed anyone on 550 since the highway began proactive avalanche control with the Colorado Avalanche Information Center in 1992. 

“Compared to other winding two-lane highways in the mountains,” Shanks said, “U.S. 550 is narrow, but that keeps speeds down. It gets relatively low volume compared to Front Range highways, so its accident rate isn’t truly high.”

Shanks said CDOT spends an average of $2 million per year on U.S. 550 between Durango and Ouray. Between 2005 and 2015, she said, there have been 412 accidents between mile marker 52 (at the base of Coal Bank Pass) and mile marker 92 at Ouray. Sixty-six accidents involved injuries, and eight brought fatalities. Surviving one of the “World’s Most Dangerous Roads” is relatively simple, Shanks said: “Know the conditions, (obey) the speed limit and, if you’re a truck diver, put your chains on.”