The U.S. Interstate Highways, Ranked

Only truckers give valentines to the U.S. interstates. Most vacationing road-trippers clog their adoration, instead, on the "blue highways," two-laners like Route 66.

Those are the ones where you feel the changing contours of the land, and drive through Main Streets that interstates miss. Who likes an interstate? After all, it's those streamlined roads, as John Steinbeck predicted bitterly in 1962, that let one "drive from New York to California without seeing a single thing."

That's hardly fair. Interstates were "the greatest public works project in history," per Earl Swift in The Big Roads. They were designed not to entertain, but to move people quickly (and safely). And yet, Steinbeck's wrong too. No interstate can outrun what's outside the window—a desert, a Rockie, a swamp, a beach, or witness that change in lighting of a southwestern dusk, or the size of a western sky, or even the steamy air in a southern night. In Roads, Larry McMurtry notes that "a thousand McDonald's will not make Boston feel like Tucson." While Robert Sullivan, who crossed the country 30 times, finds value even in familiar chains clustering exit ramps. "The real America is the farthest thing from people's minds when they are stopping for fast food," he writes without cynicism in Cross Country. "But there it is, the real America, right there."

Ranking the Lower 48's two-digit, primary interstates—66 in all, 47,000 miles (and counting)—is a subjective business. What do you make of an I-70? In parts it's bumper-to-bumper with commuters, elsewhere isolated fields of corn.

To help, we turned to algebra, and created a "traffic rating" based on vehicle travel miles per mile of interstate (1.0 is least busy, 5.0 the most). We weigh that against the general joy of the ride as a whole, often rewarding longer highways—the true "interstates"—or thematic regional rides, over mere connectors to suburbs or coastal towns.

Also, remembering the time when many roads had names (eg "Lincoln Highway") not numbers, we're suggesting new monikers for each road too. And, honestly, we can't wait to see the merch for I-10's new name, The Neck Beard.

Here we go, worst interstate to best.

Record Travel Expected For Memorial Day Weekend
I-95 near Miami. Credit: Joe Raedle via Getty Images.

66) I-95 ("Atlantic Coast Highway")

Route: 1,926 miles, Miami to Houlton, Maine
Traffic Rating: 3.74

You may have heard of a city called Philadelphia, the birthplace of the United States of America. This grueling, rarely scenic and frequently traffic-choked road wants its south-bound traffic to ignore it. This road suddenly slices mid-Jersey. Watch carefully for the lone sign directing you onto a stoplight-filled road in the suburbs to get to Philly, or you'll be ushered unaware to Delaware (and its tolls) via the New Jersey Turnpike (and its tolls).

65) I-4 ("Haunted Highway")

Route: 132 miles, Tampa to Daytona Beach, Florida
Traffic Rating: 5.0

Cutting across Florida from the Gulf of Mexico to the Atlantic Ocean via Orlando, I-4 is not only the busiest interstate in the country, but haunted. A family grave from the late 1800s was built over in 1959, followed by a flurry of traffic accidents (notably on its eastbound lanes). Watch out.

64) I-97 ("Go Navy!")

Route: 18 miles, Baltimore towards Annapolis, Maryland
Traffic Rating: 4.88

The shortest interstate in the country is the second busiest. On the plus side, it passes a town called Glen Burnie.

63) I-26 ("Mary's Curse")

Route: 306 miles, Kingsport, Tennessee to Charleston, South Carolina
Traffic Rating: 2.59

In 1916 in Erwin, Tennessee—where I-26 crosses the Appalachian Trail—Mary the Elephant was hanged by the neck from a crane after she killed her handler. And it's pretty much impossible to think of anything else the entire way through the Blue Ridge Mountains to the coast.

62) I-66 ("Stepmother Road")

Route: 76 miles, Washington, DC to some place in Virginia
Traffic Rating: 3.75

Seriously, of all interstates, this one gets "66"?

The California connection of Route 66, or the Mother Road, has captured the imagination of yester-year road-trippers for eternity. I-66, meanwhile, is an ugly commuter transport, which spans a few traffic-jammed miles before dead-ending in the Shenandoah Valley. Seriously, of all interstates, this one gets "66"?

61) I-44 ("Route 66 Killer")

Route: 634 miles, St Louis to Wichita Falls, Texas
Traffic Rating: 1.99

Tulsan Cyrus Avery helped create Route 66. Then helped kill it by creating a turnpike between Tulsa and Oklahoma City on today's I-44, believed to be the first interstate (some claim it's I-70). The scenery sure is nice—Missouri's Ozarks, and rolling Oklahoma hills that Bob Wills sung about here—but it's hard stomaching a toll in place of the Mother Road.

60) I-69 ("Bryan Adams' Rocket Science")

Route: 458 miles, Houstonish to Detroitish
Traffic Rating: 1.93

It would take a "summer of I-69" to find all the stranded bits of I-69 that stop/start in seven sections between the Houston area and north of Detroit. Start in Indiana's northwest, where the road started in the 1940s.

59) I-35 ("Central Time Zoner")

Route: 1568 miles, Laredo, Texas to Duluth, Minnesota
Traffic Rating: 2.13

The trucker-central ride from San Antonio to Dallas may be the USA's most gutting soul-crusher. To add salt, the I-35 just misses the lovely Ozarks. Larry McMurtry summed up its monotony: "even the arrival of the outlet malls is a blessing."

58) I-76 OH/PA/NJ ("The Tolled Spirit of '76")

Route: 434 miles, East Westfield Center, Ohio to Camden, New Jersey
Traffic Rating: 2.19

No number is more American than 76. Yes, this breezes by Philadelphia (and its Independence Hall), before tolling you to pieces across Pennsylvania. (A second 76 connects Denver with Nebraska.) Still, "76" deserves more, an epic cross-country road. Easy fix: swap with I-70.

57) I-45 ("The Texan Rumbleway")

Route: 285 miles, Dallas to Houston
Traffic Rating: 3.92

Dallas or Houston are not always known for exuding charm. They can duke out which has less via this road link.

Welcome to Indiana road sign against blue sky.Henryk Sadura/Getty.

56) I-65 ("Stuck Inside of Mobile with the Gary, Indiana Blues Again Highway")

Route: 887 miles, Gary, Indiana to Mobile, Alabama
Traffic Rating: 2.64

In 2007, the Chicago Bears lost to the Indianapolis Colts in the so-called "I-65 Super Bowl," named for this connection between the cities. It was a fairly dull game. And this is a fairly dull road.

55) I-2 ("The Texas-Mexico Border Road")

Route: 47 miles, Texas-Mexico border
Traffic Rating: NA

This border baby was born in 2013.

54) I-72 ("The Twain Shall Meet Abe")

Route: 179 miles, Hannibal, Missouri to Champaign, Illinois
Traffic Rating: 1.15

Fans of seeing both Mark Twain's and Abraham Lincoln's hometowns in a day benefit from this. Judging by the traffic, it's a pretty small fan club.

53) I-83 ("Barbell Byway")

Route: 85 miles, Baltimore to Harrisburg, Pennsylvania
Traffic Rating: 3.50

Harley-Davidson's biggest factory is on this guy, so is the Weightlifting Hall of Fame.

52) I-86 (PA/NY) ("Erie Express")

Route: 184 miles, Erie, Pennsylvania to Woodbury, New York
Traffic Rating: 1.31

New York lifted the number of Idaho's I-86 for its in-progress link between Woodbury Commons outlet mall and the delighted shoppers of Erie.

51) I-49 ("The Arkansas Leap")

Route: 388 miles, Lafayette, Louisiana to Kansas City (with several breaks)
Traffic Rating: 1.39

This here-and-there road is a newbie: Louisiana's fun portion, connecting swamp and suburb, came in the '80s, Missouri's US 71 turned into I-49 only in 2012. The bulk of Arkansas' stretch remains undeveloped.

50) I-74 ("Broken Road")

Route: 490 miles, Davenport, Iowa to Lumberton, North Carolina
Traffic Rating: 1.55

This interstate—hell bent on reaching the South Carolina coast one day—is split into more bits than that snake on the "Don't Tread on Me" flag.

49) I-12 ("Truck Driver's Big Easy")

Route: 86 miles, Baton Rouge to Slidell, Louisiana
Traffic Rating: 3.17 miles

This little Louisiana bypass is great if you really can't stand New Orleans, or you're in a hurry for Texas.

48) I-37 ("Padre Parkway")

Route: 143 miles, San Antonio to Corpus Christi, Texas
Traffic Rating: 1.84

Built for the beach, don't overlook George West, a mid-point town that happens to be the frickin' Storytelling Capital of Texas.

47) I-68 ("Bad Geography Byway")

Route: 113 miles, Hancock, Maryland to Morgantown, West Virginia
Traffic Rating: 1.59

Maryland's shape was created by King Charles I, who was later decapitated. That act, writes Mark Stein in How the States Got Their Shapes, was "full of good intentions," yet also full of "bad geography." The worst of that is out here, in Maryland's awkward panhandle, which droops like a mace poised for combat. Or like Charles' decapitated head, you could say.

46) I-84 PA/NY/MA ("Freedom From NYC Trail")

Route: 232 miles, Sturbridge, Massachusetts to Scranton, Pennsylvania
Traffic Rating: 3.08

Helping westward Bostonians bypass New York City.

45) I-30 ("Jerry Jones' Unauthorized Autobiography")

Route: 367 miles, Fort Worth to Little Rock
Traffic Rating: 2.72

The I-30 follows the life and times of Jerry Jones, billionaire owner of the Dallas Cowboys. He grew up in Little Rock, adopted its accent, and now rallies the Cowboys east of Fort Worth.

44) I-96 ("Michigan Tube Top")

Route: 192 miles, Detroit to Lake Michigan
Traffic Rating: 3.24

Cut across the mid-section of Michigan's "mitt," I-96 is paved atop an old Native American trail and military road from the early 1800s. It's now for commuters or beach-bound travelers.

43) I-16 ("Peachy Beachy")

Route: 167 miles, Macon to Savannah, Georgia
Traffic Rating: 1.65

Atlanta wants the water.

42) I-57 ("Somebody Really Hates the Arch")

Route: 386 miles, Chicago to SE Missouri
Traffic Rating: 1.70

This gets our award for Interstate Most Likely Not to Exist in Our Doppelganger Universe. It's not busy. It connects Chicago to soy farms. And by skipping St. Louis altogether it trims only a few miles from the parallel I-55 between Memphis and Chicago.

Highway Signs
toddmedia via Getty Images

41) I-20 ("The Other '-0' Road")

Route: 1,539 miles, San Martine, Texas to Florence, South Carolina
Traffic Rating: 2.08

"Whichever way you travel it," Larry McMurtry writes in Roads, I-20 "leads to nowhere interesting." Sorry Dallas and Atlanta.

40) I-19 ("Border Hooky")

Route: 64 miles, Nogales to Tucson, Arizona
Traffic Rating: 1.88

Vamos a Mexico.

39) I-71 ("LeBron Wants Bourbon")

Route: 344 miles, Cleveland to Louisville, Kentucky
Traffic Rating: 2.92

A diagonal stripe across the shield of Ohio, I-71 is built for function. And apparently to reach Kentucky bourbon.

38) I-73 ("Andre Not So Giant")

Route: 77 miles, Greensboro, North Carolina to Ellerbe, North Carolina
Traffic Rating: 1.0

This little guy sees itself, someday—way over a unicorn-filled rainbow in the distant future—as a direct connection between Michigan's Upper Peninsula to the South Carolina Coast. For now it's the country's least busy interstate, a wee 77-mile heart line to Andre the Giant's last home in Ellerbe, North Carolina.

37) I-59 ("Tide Roller")

Route: 445 miles, Slidell, Louisiana to Wildwood, Georgia
Traffic Rating: 1.83

This helpful southern diagonal—an aid on bigger trips between, say, the Big Apple and the Big Easy—drops by Tuscaloosa if you're looking for some Crimson Tide football.

36) I-43 ("Beat Da Bears Byway")

Route: 192 miles, Beloit to Howard, Wisconsin
Traffic Rating: 2.24

This Wisconsin road runs along Lake Michigan past Green Bay, then unexpectedly bends to avoid the Illinois border. It's the ultimate Packers connection, snubbing rival Chicago.

35) I-82 ("Columbia Connector")

Route: 144 miles, Ellensburg, Washington to Umatilla, Oregon
Traffic Rating: 1.48

I-84 meet I-90.

34) I-29 ("Creamed Wheatway")

Route: 756 miles, Kansas City to the Manitoba border
Traffic Rating: 1.32

En route from Kansas City to the Manitoba border, you can stop in Grand Forks for a bowl of creamed wheat in the birthplace of creamed wheat.

33) I-88 IL ("Hillside Strangler")

Route: 141 miles, East Moline to Hillside, Illinois
Traffic Rating: 2.25

The mash of lanes in the Chicago suburb of Hillside used to be so nuts, people nicknamed part of this road to Iowa the "Hillside Strangler" after two L.A. serial killers from the late 1970s. No crimes committed here, other than road rage.

32) I-88 NY ("Schenectady Shuffle")

Route: 118 miles, Binghamton to Schenectady, New York
Traffic Rating: 1.24

On the backside of the Catskills, the I-88 gets you to the National Soccer of Hall of Fame at Oneonta.

31. I-77 ("Hootie Highway")

Route: 610 miles, Cleveland to Columbia, South Carolina
Traffic Rating: 2.35

The only way Hootie & the Blowfish get into the Rock 'n' Roll Hall of Fame is by road trip. This one connects their hometown to the birthplace of "rock 'n' roll" in Cleveland.

30) I-86 ID ("Literal Highway")

Route: 63 miles, Idaho
Traffic rating: 1.05

This Idaho short-cut between I-84 to Pocatello goes by American Falls, named because American trappers once took a tumble over the Snake River falls here. That river's dammed, in a county named Power. Literal people in charge of names, up there.

29) I-79 ("The State of Western Pennsylvania Highway of Importance")

Route: 343 miles, Charleston, West Virginia to Erie, Pennsylvania
Traffic Rating: 1.65

Western and Eastern Pennsylvania are like two states. And this, the north-running 79, is WPA's autobahn. Best merch? Slippery Rock University ballcaps, via exit 105.

28) I-91 ("Vermont is for Lovers")

Route: 290 miles, New Haven, Connecticut to Derby Line, Vermont
Traffic Rating: 2.20

From Yale University to the Quebec line, the I-91 is the longest exclusively New England interstate, running through everybody's favorite New England state.

Westbound traffic on I-78 in New Smithville, Pennsylvania, w
Not the best time to be on I-78. Credit: Allentown Morning Call via Getty Images.

27) I-78 ("Turnpike Finger-Flipper")

Route: 144 miles, New York City towards Harrisburg, Pennsylvania
Traffic Rating: 3.53

It's hard to drive far in Pennsylvania and not pay a toll. That's where I-78 comes in, like a wink from a favorite snack-giving uncle (not in a creepy way...). It's busy sure, but passes lush green valleys that remind newly departed New Yorkers how nice it is outside their city of maggots, as Mick Jagger says. On the downside, you probably have to go to Harrisburg, Pennsylvania.

26) I-40 ("The Big 4-0")

Route: 2,555 miles, Wilmington, North Carolina to Barstow, California
Traffic Rating: 2.02

Along with I-44, this truck-heavy interstate subs for Route 66, and is the busiest (nearly) coast-to-coast ride. Yet it benefits from frequent pop-offs to original patches of the Mother Road, plus the high desert scenery of Arizona/New Mexico.

25) I-22 ("Elvis Drives")

Route: 125 miles, eventually Memphis to Birmingham, Alabama
Traffic Rating: NA

This quick southern trip connects Elvis' Graceland in Memphis; his birthplace in Tupelo, Mississippi; and Birmingham, site of his last great concert, immortalized in the bootleg Burning in Birmingham.

24) I-85 ("Biscuit Chase")

Route: 669 miles, Richmond area to Montgomery, Alabama
Traffic Rating: 3.05

In F. Scott Fitzgerald's lone travelogue, The Cruise of the Rolling Junk, he describes a 1920 roadtrip to take his wife Zelda back to her Alabama home for "peaches and biscuits." Twee, but tasty. And if you can't wait for Montgomery biscuits, take I-285 around Atlanta, and stop in Decatur at the first-ever Waffle House, restored in its 1955 splendor.

23) I-17 ("Let's Go to Phoenix!")

Route: 146 miles, Flagstaff to Phoenix
Traffic Rating: 2.68

Ponderosa pines to prickly sprouts of the saguaro cactus: not a bad scenery swap for two hours' drive on a Phoenix connection from I-40.

22) I-5 ("Great Western Teaser")

Route: 1,381 miles, San Ysidro, CA to Blaine, WA
Traffic Rating: 3.66

This busy West Coast drive sure saves you time, getting from—say— SoCal to NoCal, but it almost never sees the sea. Or the national parks. It skips San Francisco, the Cascades, and it's likely too overcast to see Mt. Rainier out your window in Washington.

21) I-89 ("Trivia Night Cheat Sheet")

Route: 191 miles, Bow, New Hampshire to Highgate Springs, Vermont
Traffic Rating: 1.57

Two states, two hard-to-remember capitals: Concord and Montpelier!

20) I-27 ("No Sleep Till Lubbock")

Route: 124 miles, Amarillo to Lubbock
Traffic Rating: 1.32

Connecting Amarillo with a dry college town named for some Texas Ranger, I-27 feels more two-laney than most interstates, with good diversions in Palo Duro State Park and Lubbock's Buddy Holly museum.

19) I-87 ("NY, I Love You, But You're Bringing Me Down")

Route: 333 miles, New York City to Champlain, New York
Traffic Rating: 2.55

No road out of New York City better gives a fed-up New Yorker a quicker bucolic thrill than I-87, following the Hudson and into the Catskills and Adirondacks.

18) I-99 ("Little Leaguer")

Route: 99 miles, Bedford, Pennsylvania to I-86 in New York
Traffic Rating: 1.40

It's the least busy, fully eastern interstate. And it's magical (I-99 runs 99 miles!). Plus it reaches the Little League World Series, at Williamsport, Pennsylvania.

Biggest negative of I-10? The original In-N-Out Burger had to be torn down to make way for it.

17) I-39 ("Custard Dagger")

Route: 306 miles, Normal, Illinois to Rothschild, Wisconsin
Traffic Rating: 1.94

Riding by Wisconsin's tidy farms and off-road signs for "cheese" is just more fun than crossing Illinois. And I-39 gets that, by yelling "phooey," skipping Chicago, cutting straight north into Wisconsin's pastoral heart.

16) I-64 ("Kentucky Derby")

Route: 954 miles, Chesapeake, Virginia to St. Louis
Traffic Rating: 2.14

Most cross-country trips take in I-40, I-70 or I-80, thus leaving out Kentucky. But I-64, the quietest ride between the Atlantic Ocean and the Mississippi River, drops by the Bluegrass State. Mighty obliged, 64.

15) I-81 ("The Appalachian")

Route: 855 miles, Dandridge, Tennessee to Wellesley Island, New York
Traffic Rating: 2.21

One of the more beautiful drives in America, and a rare gem for the east. That is, if you're not backed up in traffic.

14) I-76 CO/NE ("Uncle")

Route: 187 miles, Denver to Big Springs, Nebraska
Traffic Rating: 1.33

If you've had it with the Nebraska plains, this is the quickest ride into the mountains. But for dreamy isolated sunsets, detour to Colorado's Pawnee National Grassland.

13) I-75 ("Dixie Highway Redux")

Route: 1,786 miles, Sault Ste Marie, Michigan to Miami
Traffic Rating: 3.04

Carl Fisher, an early 20th-century can-do entrepreneur, created Miami Beach, the Indiana Motor Speedway (of Indy 500 fame), and championed an automobile taillight using gas so flammable that 15 of his factories exploded. And 100 years ago this year, he created the Dixie Highway, a parallel highway that striped America between Michigan and Florida. It's gone. So is Carl. But the I-75 is its legacy.

12) I-10 ("The Neck Beard")

Route: 2,460 miles, Santa Monica, California to Jacksonville, Florida
Traffic Rating: 2.55

Hanging as low as a neck beard on the Lower 48, the I-10 is a fun way to connect the coasts—and particularly useful when other trans-continental ways are covered in ice. Great towns: New Orleans, San Antonio, underrated El Paso, Los Angeles. Excellent nature: Florida's white sands at Pensacola, Texas hill country, Joshua Tree National Park. (Biggest negative? The original In-N-Out Burger had to be torn down to make way for it.)

11) I-93 ("New Hampshire Ruler")

Route: 190 miles, Boston to St. Johnsbury, Vermont
Traffic Rating: 3.26

Before the interstate was paved, there was concern traffic would deface the "Old Man of the Mountain" formation in Franconia Notch State Park, right off the road in New Hampshire's woodsy glory. Actually it did fall, in 2003, but from natural erosion not traffic.

Aerial view of Mission Bay, San Diego
f8grapher via Getty Images​​​​​​​

10) I-8 ("Sweetheart Plank")

Route: 348 miles, San Diego to Casa Grande, Arizona
Traffic Rating: 1.66

This southwest short-cut crosses some desolate, fascinating country: the Sonoran Desert, Yuma foothills, ghost towns around the Algodones Dunes, and an old plank road that turned 100 this Valentine's Day.

9) I-94 ("Fargo Forever")

Route: 1,585 miles, Billings, Montana to Port Huron, Michigan
Traffic Rating: 2.08

All it really takes to "get" the Great Plains—those seas of wheat that gently roll over prehistoric sea floors—is to try. (Emily Post, an etiquette writer, wrote about her 1915 cross-country drive, summing them up as offering "an impression of the lavish immensity of our own country as nothing else could.") To see the light, try this epic sky drive across North Dakota. A great detour is the "Enchanted Highway," an iron-sculpture lined two-laner to Regent, North Dakota.

8) I-15 ("Rock Skipper")

Route: 1,433 miles, San Diego to Sweet Grass, Montana
Traffic Rating: 2.32

Sure, most people know I-15 as the road to Vegas, but its northeastern climb offers a main artery to national park central: Death Valley, Zion, Bryce Canyon, Yellowstone, Glacier. God, it's fun driving across the west.

7) I-25 ("Wyoming Autobahn")

Route: 1,063 miles, Las Cruces, New Mexico, to Buffalo, Wyoming
Traffic Rating: 1.73

It's often Rockies out one window, high plains out the other, before finishing with a legal 80 mph ride into Buffalo, Wyoming, home to one real-deal Wild West hotel.

6) I-55 ("Jesus Just Left Chicago")

Route: 964 miles, Chicago to Laplace, LA
Traffic Rating: 2.0

It's Jesus' favorite interstate according to ZZ Top's 1973 song, "Jesus Just Left Chicago." It's covers hallowed ground too, tracing one of Amtrak's legendary routes. It follows old Route 66 through Lincoln Central at Springfield; then buddies up with the Mississippi to Memphis, before cutting across the Delta towards the Big Easy.

In Nebraska, I-80 has a 72-mile stretch without a single turn.

5) I-80 ("Lincoln Highway Redux")

Route: 2,890 miles, San Francisco to Teaneck, New Jersey
Traffic Rating: 1.93

Interstates are often defined by their middles. And much of I-80, more or less the realized version of the Lincoln Highway, is flat and repetitious. Nebraska has a 72-mile stretch without a single turn. Look closer. In Wyoming, where the road cuts through pink granite rock huddling the sides of the road, watch for the "gangplank," a slow rise in the high plains. As John McPhee put it in Rising from the Plains, "At this place, as nowhere else, you can step off the Great Plains directly onto a Rocky Mountain summit."

4) I-24 ("The Legend")

Route: 316 miles, Pulley's Mill, Illinois to Chattanooga, Tennessee
Traffic Rating: 2.54

If you need a challenge, I-24's "Monteagle Mountain," a 6 percent grade in Tennessee, is considered the most treacherous stretch on the interstates. Jerry Reed, underrated star of Smokey and the Bandit, wrote a song for it ("The Legend"). Johnny Cash also sang of it too: "your life is in your hands when you start down that long steep grade."

3) I-84 OR/ID/UT ("Big Country")

Route: 770 miles, Portland, Oregon to Echo, Utah
Traffic Rating: 1.33

The least busy interstate of more than 500 miles, the gorgeous I-84 of the west offers the system's most dramatic blink-and-you-miss-it interstate view. An hour east of Portland, keep an eye for the 523-foot drop of Multnomah Falls, a few hundred feet out your car window.

2) I-70 ("Trans-Siberian American")

Route: 2,153 miles, Baltimore to Cove Fort, Utah
Traffic Rating: 1.87

Poor I-70. Patches of this nearly trans-continental monster strike horror into backseat groaners on long trips. Kansan plains, in particular, where winds can topple 18-wheelers. That said, no other interstate has done more. After crossing the Midwest, it catches the greatest skyline-from-interstate view in St Louis (the Mississippi meets Arch, right by the road), then slowly rises over the big-sky plains and runs smack into the heart of the Rockies – just the Glenwood Canyon leg requires three tunnels and 39 bridges – before finishing in the Utah desert at I-15.

The Chicago skyline is seen from I-90 De
AFP/Getty Images​​​​​​​

1) I-90 ("America's Great Road")

Route: 3,102 miles, Boston to Seattle
Traffic Rating: 1.67

I-90 needs to fire its Brand Manager. As the USA's longest interstate, it is the King of the Plains, Big Sky Central, the Northern Delights, or perhaps the Road Not to Take in Winter.

But we think of it simply as America's Great Road.

If you are going to make one cross-country trip in your life, look close at I-90. Robert Sullivan, author of Cross Country, has gone coast to coast at least 30 times, and picks this as his favorite. It's less trafficked than I-10, I-40, I-70, I-80 (the other four main east/west options). On its way, it goes from Boston's Freedom Trail to almost within the spray of Niagara Falls, into rock'n'roll HQ in Cleveland then Chicago, across the plains to Wall Drug's throw-back free water and Mt Rushmore, to the world's first dude ranch, past Custer's last stand at Little Bighorn, over Idaho's Fourth of July Summit, and reaching birthplace of something called Starbucks.

We bow to you I-90, the greatest interstate in the USA.

Robert is the Digital Nomad for National Geographic Traveler and host of the 76-Second Travel Show for his website He lives in Portland, Oregon, and really is in the mood for a long drive.