Longest Signed Single Lane Highway in the U.S.

[Max Rockatansky]

Example; CA 4 from near Pacific Grade Summit east to CA 89 has an unbroken single lane/no center stripe segment.  What are some other examples of lengthy single lane Signed Highways in the United States?

Edit:  For simplicity sake Forest Routes signed with reassurance shields will be excluded from the criteria.  Upon revisiting this thread I can probably think of a couple that would blow State Routes and County Routes out of the water in terms of paced single lane distance. 

[hotdogPi]

I knew this was going to become a thread.

[Max Rockatansky]

It's what I thought the longest single lane thread was about when I read the title the first time. 

[kphoger]

Example; CA 4 from near Pacific Grade Summit east to CA 89 has an unbroken single lane/no center stripe segment.  What are some other examples of lengthy single lane Signed Highways in the United States?

What's the length?

[Max Rockatansky]

Example; CA 4 from near Pacific Grade Summit east to CA 89 has an unbroken single lane/no center stripe segment.  What are some other examples of lengthy single lane Signed Highways in the United States?

What's the length?

About 20-25 miles, I didn't have access to the Postmile Tool and was going to edit it in later.  There is about a mile or two lane that breaks it up from being about 30 west to CA 207.

Edit: Eyeballing it from my notes it's closer to 20 miles and expands back to two lanes near Silver Mountain City a couple miles from CA 4.

https://www.gribblenation.org/2018/08/trans-sierra-highways-california-state.html?m=1

[oscar]

Maui County 340, around the northwest corner of Maui island, is about 9.4 miles long, and most of was one-lane last time I drove it. However, there are some wide spots in the road (especially in Kahakuloa village), one of which has a center stripe. Also, it's been awhile since I've driven that road, and parts of it might've been widened since then, so I don't know how much of it is still one-lane.

Some other highways in Hawaii, like HI 360/county 31 in east Maui and HI 560 along Kauai's north shore, have a lot of one-lane bridges, but there's usually a center stripe between the bridges.

[kphoger]

Hmmm... Need some clarification.  I'm thinking of some roads that have edge lines but no center stripe–yet they're plenty wide enough for two vehicles.  Is that a single-lane road or a two-lane road?  (These are not signed as highways, so they're not candidates for the thread.  I'm just getting my brain spinning on it.)

[Max Rockatansky]

Hmmm... Need some clarification.  I'm thinking of some roads that have edge lines but no center stripe–yet they're plenty wide enough for two vehicles.  Is that a single-lane road or a two-lane road?  (These are not signed as highways, so they're not candidates for the thread.  I'm just getting my brain spinning on it.)

Let's go simple, if it doesn't have a center stripe but is a Signed Highway it qualifies.  The CA 4 example I gave certainly is wide enough for two cars to pass each other carefully. 

[roadman65]

PR 3 climbing over the mountain on the SE Corner of Puerto Rico has one lane for several miles.   

[Max Rockatansky]

Some others that came to mind; all are shorter than CA 4:

-  SD 87 on the Needles Highway segment through Custer State Park.
-  The entirety of CA 172.
-  The south segment of CA 229. 
-  Western CA 146 from Monterey County Route G15 to the boundary of Pinnacles National Park.
-  M-185

A lot of M-119 from Harbor Springs is a single lane but I'm uncertain if it tops CA 4. 

[interstatefan990]

Hate to be a buzzkill, but would these really be considered "single lane" highways? I'd be more inclined to classify the roads mentioned in this thread as normal highways that just don't have lanes (no center line). There is two-way traffic, and all vehicles keep to the right side in accordance with the law and so that they can safely pass oncoming vehicles. If I were to imagine what a true "single lane" highway looks like, it would seem like a freeway on-ramp, with one-way traffic and not enough width for two-way, but it never actually takes you onto a freeway. I have never seen an example of a road like that being an actual mainline highway, though.

[Max Rockatansky]

Hate to be a buzzkill, but would these really be considered "single lane" highways? I'd be more inclined to classify the roads mentioned in this thread as normal highways that just don't have lanes (no center line). There is two-way traffic, and all vehicles keep to the right side in accordance with the law and so that they can safely pass oncoming vehicles. If I were to imagine what a true "single lane" highway looks like, it would seem like a freeway on-ramp, with one-way traffic and not enough width for two-way, but it never actually takes you onto a freeway. I have never seen an example of a road like that being an actual mainline highway, though.

This is normal to you?

https://www.gribblenation.org/2018/08/trans-sierra-highways-california-state.html?m=1

If so, tell me where I can find more just like it. 

[interstatefan990]

Hate to be a buzzkill, but would these really be considered "single lane" highways? I'd be more inclined to classify the roads mentioned in this thread as normal highways that just don't have lanes (no center line). There is two-way traffic, and all vehicles keep to the right side in accordance with the law and so that they can safely pass oncoming vehicles. If I were to imagine what a true "single lane" highway looks like, it would seem like a freeway on-ramp, with one-way traffic and not enough width for two-way, but it never actually takes you onto a freeway. I have never seen an example of a road like that being an actual mainline highway, though.

This is normal to you?

https://www.gribblenation.org/2018/08/trans-sierra-highways-california-state.html?m=1

If so, tell me where I can find some more of them.

Well, I meant normal for the purposes of classifying them as two-way highways, but in a state famous for having some of the worst traffic and air pollution around in some parts, I'm sure CA 4 is a wonderful and welcome escape from "normal". 

[Rick Powell]

Iroquois County in IL once had dozens of miles of 10-foot wide concrete state highways with gravel passing shoulders. The story I heard was an ancient state law that required absorption into the state highway system if a local agency built them to the 10-foot minimum spec. They have all been widened and transferred back to the county under a program to rid the state of those routes, the last one around 10 years ago.
https://www.daily-journal.com/news/local/slab-roads-slowly-becoming-extinct/article_03877873-4131-54d2-8e37-abe40abce2a8.html

[dlsterner]

Well, if you are willing to accept a highway as "Signed" with a name rather than with a number ...

Outside of Gatlinburg TN, there is the "Roaring Fork Motor Nature Trail" which winds for about 6 miles (give or take) as a one-way, one-lane road.

It's mostly posted at 10 mph so it takes about an hour to drive, if you don't stop at some of the sights along the way.  It's a very nice drive.

[jakeroot]

Maui County 340, around the northwest corner of Maui island, is about 9.4 miles long, and most of was one-lane last time I drove it. However, there are some wide spots in the road (especially in Kahakuloa village), one of which has a center stripe. Also, it's been awhile since I've driven that road, and parts of it might've been widened since then, so I don't know how much of it is still one-lane.

Some other highways in Hawaii, like HI 360/county 31 in east Maui and HI 560 along Kauai's north shore, have a lot of one-lane bridges, but there's usually a center stripe between the bridges.

My first thought was also Maui.

I personally remember significant portions of Piilani Hwy south and (primarily) west from Hana (in addition to the Hana Hwy) as being single-lane, although a fair amount was closer to 1.5 lanes. Good street view imagery. It is now a very high quality road, although still fairly narrow. The old road was ... well, it was basically undriveable in a regular car. The new road was nice enough that I was able to plow along well enough that I occasionally forgot what the speed limit was.

Edit: they've jerry-rigged in some two-lane stretches, which seem to have laughably-narrow lanes.

[TheGrassGuy]

Considering how windy the mountain roads are there, I'd speculate that the record-holder is somewhere in China.

[TheGrassGuy]

My first thought was also Maui.

I personally remember significant portions of Piilani Hwy south and (primarily) west from Hana (in addition to the Hana Hwy) as being single-lane, although a fair amount was closer to 1.5 lanes. Good street view imagery. It is now a very high quality road, although still fairly narrow. The old road was ... well, it was basically undriveable in a regular car. The new road was nice enough that I was able to plow along well enough that I occasionally forgot what the speed limit was.

Edit: they've jerry-rigged in some two-lane stretches, which seem to have laughably-narrow lanes.

There in 2009.

[Max Rockatansky]

Hate to be a buzzkill, but would these really be considered "single lane" highways? I'd be more inclined to classify the roads mentioned in this thread as normal highways that just don't have lanes (no center line). There is two-way traffic, and all vehicles keep to the right side in accordance with the law and so that they can safely pass oncoming vehicles. If I were to imagine what a true "single lane" highway looks like, it would seem like a freeway on-ramp, with one-way traffic and not enough width for two-way, but it never actually takes you onto a freeway. I have never seen an example of a road like that being an actual mainline highway, though.

This is normal to you?

https://www.gribblenation.org/2018/08/trans-sierra-highways-california-state.html?m=1

If so, tell me where I can find some more of them.

Well, I meant normal for the purposes of classifying them as two-way highways, but in a state famous for having some of the worst traffic and air pollution around in some parts, I'm sure CA 4 is a wonderful and welcome escape from "normal". 

The weird part about CA 4 is that it has several freeway segments and isn't much wider in the San Joaquin River Delta as Ebbetts Pass.  All it's missing is a dirt or gravel segment to complete the full range of highway diversity. 

[tq-07fan]

WV 82. There is a one lane portion that winds around and under THE New River Bridge from the Visitor's Center to Fayetteville. It is One Way only and one lane with pull offs for around six miles.

Map

Cool, figured out how to post the url as Map without all the other stuff!

Jim

[Max Rockatansky]

Maui County 340, around the northwest corner of Maui island, is about 9.4 miles long, and most of was one-lane last time I drove it. However, there are some wide spots in the road (especially in Kahakuloa village), one of which has a center stripe. Also, it's been awhile since I've driven that road, and parts of it might've been widened since then, so I don't know how much of it is still one-lane.

Some other highways in Hawaii, like HI 360/county 31 in east Maui and HI 560 along Kauai's north shore, have a lot of one-lane bridges, but there's usually a center stripe between the bridges.

My first thought was also Maui.

I personally remember significant portions of Piilani Hwy south and (primarily) west from Hana (in addition to the Hana Hwy) as being single-lane, although a fair amount was closer to 1.5 lanes. Good street view imagery. It is now a very high quality road, although still fairly narrow. The old road was ... well, it was basically undriveable in a regular car. The new road was nice enough that I was able to plow along well enough that I occasionally forgot what the speed limit was.

Edit: they've jerry-rigged in some two-lane stretches, which seem to have laughably-narrow lanes.

That undrivable segment looks like something that would be up my alley. 

[kphoger]

Considering how windy the mountain roads are there, I'd speculate that the record-holder is somewhere in China.

Considering that the title of this thread has the phrase "in the U.S.", I'd speculate that the record holder is somewhere in the U.S.