Most dramatic contrasts on a single route in a single state

[STLmapboy]

MO-21. Starting at Arkansas Route 115, the majority of 21 is a two-lane winding road through the Ozarks that then blossoms to 2000s-constructed four-lane expressway from Hillsboro to the Meramec River/141. The latter section was constructed to replace the rather dangerous Old Route 21, nicknamed Blood Alley, which still flirts with the expressway on its original routing. It has long been proposed to expand the expressway from its current stub in Hillsboro further south to DeSoto, but nothing has come to fruition. MO-21 crosses 270 and enters STL suburbia as Tesson Ferry Rd, with a rather unceremonious ending at MO 30-Gravois Rd in Affton.

[tdindy88]

I would suggest for Indiana SR 135. It begins at a bridge over the Ohio River and runs north through fairly hilly terrain through Harrison and Washington Counties, passing by historic Corydon and (until recently) around a historic courthouse square in Salem (which has been bypassed since.) After continuing north to US 50 in Brownstown (another county seat) the highway then runs through an area deep in the Hoosier National Forest, a low-count highway with lots of bends and turns through Jackson and Brown Counties. Once it arrives in another popular town, Nashville the highway continued north through the hills of Brown County, now serving as a route between Nashville and Indianapolis. North of Morgantown the terrain suddenly flattens out and the highway runs through terrain similar to the central part of the state through Johnson County. Near Greenwood the highway widens and it serves a large commercial district, running through the south side along Meridian Street before finally terminating near US 31 and I-465, more than 100 miles from the Ohio River. In older times the highway used to continue up Meridian Street all the way to Downtown Indianapolis, connecting Indiana's first capital city with its current capital.

[Bickendan]

US 26 in Oregon, hands down, and it used to be better before it was truncated from Astoria to the interchange with US 101 between Cannon Beah and Seaside.

[Konza]

AZ 87 and I-17 deserve honorable mentions.

If US 80 hadn't been decommissioned, it would merit consideration in Arizona as well.

Sky Islands.  The border at Douglas.  Bisbee.  Tombstone. Chihuahuan desert.  Tucson.  Sonoran Desert.  Phoenix.  More Sonoran Desert.  Yuma and the border again.

[Jmiles32]

Route 28 is another good example in Virignia that I'd like to nominate. Starts off as rural two-lane road with about 10,000 AADT and within 50 miles is an eight-lane expressway (with plans to get wider) that carries over 164,000 AADT and is constantly conjested.

Southern terminus near Remington:
https://www.google.com/maps/@38.5637148,-77.7994717,3a,45y,32.7h,88.31t/data=!3m6!1e1!3m4!1sJXp_Er2A4OC6YO2KGemDGA!2e0!7i16384!8i8192?hl=en

Middle Segment near Manassas:
https://www.google.com/maps/@38.7820008,-77.4500608,3a,27.4y,11.4h,85.65t/data=!3m6!1e1!3m4!1sK8tZzfUsib1E9Qeq4I7SnA!2e0!7i16384!8i8192?hl=en

At the VA-267 interchnage near Dulles Airport:
https://www.google.com/maps/@38.9667618,-77.4288761,3a,35.6y,182.1h,85.78t/data=!3m6!1e1!3m4!1sI1iE8mZPDt8RQh5PDZcoKg!2e0!7i16384!8i8192?hl=en

[gonealookin]

Not a lot of good candidates in Nevada so I suppose I'll settle for US 95.  Urban freeway and high speed expressway in the south and also coincides with Interstate 80 for some distance in the north.  The rest is two-lane road with AADT not much more than 2000 in some areas, generally near Tonopah in the central part of the state.  None of it goes through mountains though and the only short stretch that's the least bit winding is the few miles alongside Walker Lake just north of Hawthorne.

[Max Rockatansky]

Not a lot of good candidates in Nevada so I suppose I'll settle for US 95.  Urban freeway and high speed expressway in the south and also coincides with Interstate 80 for some distance in the north.  The rest is two-lane road with AADT not much more than 2000 in some areas, generally near Tonopah in the central part of the state.  None of it goes through mountains though and the only short stretch that's the least bit winding is the few miles alongside Walker Lake just north of Hawthorne.

US 50 has some pretty decent variation itself given it begins as an expressway from the California State Line and is a freeway in the Carson City Area.  US 50 east of Fallon towards Ely has become infamously desolate (even though I'd give the lonely moniker to US 6 between Tonopah-Ely) and doesn't resemble anything other than a hyper remote US Route by the Utah State Line.

[Max Rockatansky]

With Florida I'd say US 27 has the most variations in regards to geographic.  US 27 is a major urban surface street in Tallahassee, goes through a remote of the Gulf Coast region, the Ocala Plateau, the Everglades, before ending in downtown Miami. 

[jp the roadgeek]

I nominate I-95 for CT.  It's 8 and 10 lanes through most of Fairfield County and 6-8 lanes through the New Haven area.  But the area east of Branford; especially from Groton to the RI border, is mostly desolate (save for New London), despite the latter being within 20 minutes of two casinos, Mystic Seaport and Aquarium, and the RI beaches. 

[amroad17]

For interstates, I-64 for Virginia.

The 299 mile long highway enters the western part of the state from West Virginia, traversing through the eastern part of the Appalachian Mountains, carrying below 10,000 AADT in most areas, the lightest traveled interstate in the state.

On the opposite end however, I-64 is the main interstate highway in the Hampton Roads metropolitan area, in many places 8 lanes or wider, carrying well over 100,000 AADT in many areas, dropping to around 90,000 AADT on its eastern end (near Bowers Hill in Chesapeake). The interstate traverses through Williamsburg, Newport News and Hampton on the Peninsula, then crosses the Hampton Roads harbor on the Hampton Roads Bridge Tunnel (HRBT) to serve the Southside cities of Norfolk, Virginia Beach, and Chesapeake. Four auxiliary interstates, the only ones of I-64 in the state, I-264, I-464, I-564, and I-664 serve the other cities, Suffolk and Portsmouth, and connects other areas not served directly by I-64.

I-64 is the main route used east of I-295 (Richmond), carrying over 60,000 AADT and much higher during peak weekends on only 4 lanes, for tourists bound to the Virginia Beach oceanfront and further south to the Outer Banks via VA-168, NC-168, and US-158, both popular destinations during the summer. Efforts are currently underway to widen the entire corridor to 6 lanes between I-295 and Newport News to 6 lanes, and since 2017, nearly 20 miles have been complete, with an additional 8 miles underway near Williamsburg, which will leave only 27 miles left to be funded and constructed.

And, along with what sprjus4 has posted, I would say US 60 in Virginia.  Enters the Commonwealth on a freeway (with I-64) in the mountains, becomes a (mostly) two-lane road through Lexington and throughout the rest of the Appalachians, goes through smaller towns and country areas between the mountains and Richmond, goes through Richmond as a main city street, is mostly a four-lane arterial from Richmond, through Williamsburg, Newport News, and Hampton, joins I-64 for an excursion over Hampton Roads on the HRBT, again leaves I-64 in Norfolk for some beach- and oceanside four-lane arterials until the resort section in Virginia Beach, at which it is a local street, with its shops, hotels, and some residences to its end at Rudee Inlet.

[noelbotevera]

My vote for Pennsylvania goes to US 30. Fairly nondescript winding road, major freeway through Pittsburgh (and was the first designation with US 22; I-376 came later), suburban hell more or less to Irwin (does manage to get nice bridges in East Pittsburgh). East of Irwin/Greensburg US 30 reverts to a free alternate to the PA Turnpike, still a nondescript country road. East of Bedford somehow US 30 is an expressway, despite said expressway ending short of everyone's favorite town. Once again a normal 2 lane road (most truck traffic is on I-70, regional traffic on the Turnpike) winding through mountains, until the terrain flattens out at PA 75 in Fort Loudon. It's also the final hurrah for US 30's mountain climbing after its Oregonian beginnings.*

In central PA, US 30 serves as the lifeblood for Amish Country, passing through Chambersburg, Gettysburg, York, etc. East of York, US 30 becomes a freeway and stays that way until the Philadelphia area; although a 17 mile freeway gap exists due to Amish NIMBYs. East of US 202, US 30 reverts to a 4 lane road and is practically suburban hell entering Philadelphia. It has one final role as Girard Avenue, a major street in West Philadelphia (born and raised, in the playground...) until it jumps onto the freeways into New Jersey, spending time on the Schuylkill (or Surekill) and Vine Street Expressways.

*The mountains east of Chambersburg aren't really mountains; yes there's climbing lanes but no runaway truck ramps/grade signs posted, so it's more like a long hill than a mountain. Can easily maintain 50+ MPH there.

Maybe not as diverse as US 60 in Virginia (why not US 58?), US 45 in Illinois, or even US 30 in Oregon, but still quite the (long) journey.

[sprjus4]

(why not US 58?)

Pretty much the same throughout the state, mix of 2 to 4 rural divided lane highway passing through some towns while bypassing others, with a small 20 mile concurrency with I-81 between Bristol and Abingdon. Crosses I-81, I-77, I-85, and I-95 along its path and picks up traffic volumes heading east, though doesn't really spike above 20,000 AADT until around Courtland / Franklin.

Largely serves as a divided highway between I-77 and Hampton Roads serving local communities and a couple medium sized cities such as Danville along its path, with through traffic largely using I-81 and I-64 for cross-state travel. It does serve as the main outlet from I-85 and I-95 from the south to Hampton Roads on the eastern portion, though even then doesn't see the large numbers that I-64 sees coming into Hampton Roads from the northwest.

The only "dramatic contrast" portion would be on the eastern tip in Hampton Roads where it becomes a major freeway around Suffolk and towards I-64 (though with a few intersections remaining so not technically "freeway" but 60 mph expressway), then into a local 2 to 8 lane roadway paralleled by I-264 through Portsmouth, Norfolk, and Virginia Beach.

I suppose it could work.

[jmacswimmer]

I-270 in MD goes from this to this in the span of 10 miles - Still a heavily-used commuter route throughout, but how quickly it shrinks from a 12-lane local-express setup to a 4-lane freeway is really something (something that urgently needs correcting, FWIW!).

That said, I think the best example in MD is US 50.  Briefly cuts thru rural, mountainous Garrett County in the panhandle, then after passing thru WV VA & DC, returns to MD as a busy commuter route and passes thru this large turbine interchange with the Capital Beltway.  US 50 then continues to Annapolis with unsigned I-595 along for the ride, hitting some of Annapolis suburbia, before passing over a certain well-known bridge and becoming the primary beach route.  US 50 then continues across the Delmarva Peninsula as a mostly at-grade expressway, passing directly thru Cambridge and bypassing Salisbury as a freeway, before finally arriving in Ocean City.

[ethanhopkin14]

US-67 in Texas goes from being a rural 2-lane road in West Texas to being multiplexed with the busy I-35E and I-30 freeways in Dallas.

LA-1 in Louisiana is a rural 2-lane road in most of the state, but is one of the main north-south arteries in Shreveport.

Also SH 114.  It "enters" Texas (from New Mexico 114) as a dusty panhandle two lane road, and with the help of some multiplexes and the Lubbock area, it graduates to a 4 lane and expressway highway, then it goes back to a 2 lane highway.  When it's all said and done, it finishes it's life as the John Carpenter Freeway and a major freeway link between Dallas and Ft Worth.

Also US 90.  From it's western terminus in Van Horn to Marfa, it's a West Texas lonely 2 lane highway that you could literally lay down in the middle of for several minutes without feeling like you would get flattened.  When it reaches San Antonio, it is a full fledged interstate grade freeway. 

[zachary_amaryllis]

i feel like the desert, is pretty in its own way..

i've been through nv once, on I-80, and what impressed me was how far out in the middle of nowhere stuff is.. i mean, in kansas you can see farmhouse lights in the distance at night.. on i-80, not so much.

Not a lot of good candidates in Nevada so I suppose I'll settle for US 95.  Urban freeway and high speed expressway in the south and also coincides with Interstate 80 for some distance in the north.  The rest is two-lane road with AADT not much more than 2000 in some areas, generally near Tonopah in the central part of the state.  None of it goes through mountains though and the only short stretch that's the least bit winding is the few miles alongside Walker Lake just north of Hawthorne.

[frankenroad]

I'd also nominate US-50 in Ohio, which goes from an urban freeway in downtown Cincinnati, to a parkway to a 2-lane road through much of the rest of the state. 

But I agree with the earlier poster who mentioned OH-315 because the whole route is not that long (maybe 25 miles) and the change is very sudden.

[hbelkins]

US 60 in Kentucky.

Full freeway around Owensboro, urban thoroughfare in Lexington and Louisville, narrow curvy two-lane for the most part between Mt. Sterling and the Ashland area.

US 50 in West Virginia. Full freeway at Parkersburg and Clarksburg, mountainous two-lane east of Clarksburg/Bridgeport.

[TEG24601]

US 12 in WA - From the tide flats of the Pacific Ocean, through the western steppe, through the south end of the Puget Sound Basin, over the Cascade mountains, then through the high desert of Washington, and then into the fertile valleys if Idaho.  From one-way couplets at US 101, to rural expressway, to 2-lane road, to 6 Lane Interstate Freeway, to 2-lane road again, more Freeway, 2-lane road, and more couplets.

[GaryA]

CA 4 goes from far flung one lane seasonal mountain pass to a levee bound highways in the Sacramento River Delta before becoming a major urban freeway near the Carquinez Strait.  The historic extent of CA 2 would probably be the only real contender given current CA 173 and it's dirt segment were part of the highway.  CA 1 doesn't quite go down to the level of CA 4 over Ebbetts Pass but it highly contrasts from rural coast road to urban freeway in places like Monterey and the San Francisco Peninsula.

CA 33 might also be a contender here, going from a freeway to a mountain highway, then in the Central Valley going past oil fields, scrubland, cattle ranches, and farmland.

[74/171FAN]

I would pick US 6 for Pennsylvania.  What is mostly a two-lane country road (with the exception of Meadville where it has a four-lane section concurrent with US 19 and US 322 and the US 62 concurrency) becomes a four-lane arterial (minus Clarks Summit proper) concurrent with US 11 then a freeway concurrent with I-81 before having its own freeway segment on the Carbondale Bypass.  Then it goes back to a two-lane country road as it parallels I-84.

When it comes to PA State Routes, I would pick PA 114.  Its western part from PA 944 to PA 641 in Mechanicsburg is a major route (being expressway from PA 944 to US 11, including a 4-lane section with a 55 mph speed limit).  East of US 15, it is a windy route that I really wonder if it should even exist even as it connects to I-83 (just south of the I-76/PA Turnpike Interchange) and the Capital City Airport.

[6a]

Can we add provinces? I'd nominate 401 in Ontario. 4 lane rural freeway outside of Windsor to however the hell many lanes in Toronto.

[skluth]

MO-21. Starting at Arkansas Route 115, the majority of 21 is a two-lane winding road through the Ozarks that then blossoms to 2000s-constructed four-lane expressway from Hillsboro to the Meramec River/141. The latter section was constructed to replace the rather dangerous Old Route 21, nicknamed Blood Alley, which still flirts with the expressway on its original routing. It has long been proposed to expand the expressway from its current stub in Hillsboro further south to DeSoto, but nothing has come to fruition. MO-21 crosses 270 and enters STL suburbia as Tesson Ferry Rd, with a rather unceremonious ending at MO 30-Gravois Rd in Affton.

MO 21 definitely has contrasts, but I think MO 7 has more. It's a dangerous winding rural road through the Ozarks from its SE terminus as a rural I-44 exit near Fort Leonard Wood to expressway in its concurrency with MO 5 through Camdenton then back to winding two-lane rural road to Clinton to the primary road on an expressway to Harrisonville to a flatland rural road though farm fields to the main N-S axis in Blue Springs to its exurban/rural north terminus at the US 24 expressway interchange.

I know MO 21 also has another stretch of expressway concurrent with US 60 (I've driven it a few times), most of the MO 21 traffic is headed to US 60 while the MO 5/MO 7 concurrency has a lot of traffic on each end but little traffic on either road goes much beyond the Camdenton expressway; most of the traffic originates from US 54 through Lake of the Ozarks and MO 5 is nominally the main road. I could also make arguments for MO 13, MO 94, MO 100, US 169, and especially US 61. I've driven all of MO 94 (one of my favorite state drives west of St Chuck) and MO 100 and almost all of US 61 in MO. I'd say every one has more extremes than MO 21, though it definitely has its contrasts.

I've been to Johnson's Shut-Ins a few times and my ex's sister lived just outside De Soto, so I've driven MO 21 several times back when I lived in St Louis. I was happy when I found out that it's easier to drive to Taum Sauk via US 67 and cutting over from Park Hills or Farmington.

Off-topic, but I do wish they'd complete US 50 as an expressway across the state. It would pull a ton of traffic off I-70, especially from those going from South City and South County to the Lake or State Fair. I used it for that even though it's a crappy two lane road west of Union until almost Jeff City. It's actually a pretty good alternate even going all the way across the state to KC when I-70 has a construction headaches, especially on holiday weekends (except during the MO State Fair).

[doorknob60]

US-33 and US-35 in Ohio go from two lane roads going through small towns on the western side of the state to being expressways and interstate grade facilities through the mountains of eastern Ohio.

US-30 is the inverse, it is a two lane mountain road in the east and becomes the only at grade route (other than US-33) to have a 70 mph speed limit east of the Mississippi in the plains of west Ohio.

I think top honors in Ohio go to OH-315, which is a six-lane urban freeway within the Columbus beltway and a rural two-lane road between the beltway and its northern terminus with US-23 in Delaware.

That was the first thing that came to mind, I just drove that on Wednesday. And the transition between semi-rural and urban is fast, that's the most dramatic part.

[froggie]

In Minnesota it's probably MN 65, originating in the heart of downtown Minneapolis at the south end, while near the north end parts of the route weren't paved until 2000.

There was about a 7 year period in the 1990s where MN 65 had both freeway (Cambridge bypass) and unpaved (Nett Lake).

[hobsini2]

83 is good in Illinois but I think 53 is better.

Starts at Gardner as a 2 lane country road until Wilmington. 4 lane divided highway from Wilimington to I-80 in Joliet. 4 lane street and one way streets in Joliet. 4 lane road through Romeoville, Bolingbrook (6 lane at I-55), Woodridge and Lisle. 2 Lane road though the Morton Arboretum and unicorp Glen Ellyn and Lombard. 4 lane Divided/undivided highway again from North Ave to and on Biesterfield Rd before joining I-290. One 290, it is 8-10 lanes up to Kirchoff Rd before going to 6 lanes to Dundee Rd. Exiting at Dundee then going up Hicks Rd as a 2 lane road before ending at Route 83.