# Meaning of Solid Line (on the Road)... **URL:** \ **Category:** Factual Questions\ **Created:** [July 10, 2013, 7:02am UTC](https://boards.straightdope.com/t/meaning-of-solid-line-on-the-road/663109 "2013-07-10T07:02:35Z")\ **Posts on this page:** 17\ **Page:** 2
**Author:** ![garygnu](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/garygnu/32/2924_2.png) [@garygnu](https://boards.straightdope.com/u/garygnu)\ **Post date:** [July 10, 2013, 2:37pm UTC](https://boards.straightdope.com/t/meaning-of-solid-line-on-the-road/663109/21 "2013-07-10T14:37:08Z")
> [@CookingWithGas](#): > > Double solid lines are commonly found on interstate HOV lanes where they prohibit traffic from moving freely in and out of the HOV lane. I do not know what states have this but Virginia and Maryland are two examples. > … There are limited entry/exit HOV/Diamond lanes in the Los Angeles area that use double solid white lines, with Bott Dots in between the lines. ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [July 10, 2013, 2:53pm UTC](https://boards.straightdope.com/t/meaning-of-solid-line-on-the-road/663109/22 "2013-07-10T14:53:25Z")
> [@](#): > > Maybe Europe is different than the USA. In my experience, one-way roads are extremely common at the exit/entrance ramps to an interchange, and as traffic-control measures in busy streets, and in general for unusually narrow roads. But I’d never expect a two-lane country road to be one-way. Maybe not a two-lane country road, but often large highways will diverge around natural obstacles, so where you had two lanes in each direction across a four-lane road, it splits off into two lanes into two roads, quite often not visible from each other (like when there is a wood in between), before meeting up again some ways down the road. If you’re not familiar with the area and merge onto such a highway, you can sometimes be confused as to whether you’re on a two lane highway with one lane in each direction, or on a two-lane highway with both going the same way. I know that I’ve been on roads where I asked myself, “shit, is this one-way or two-way?” ---
**Author:** ![Hermitian](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hermitian/32/470_2.png) [@Hermitian](https://boards.straightdope.com/u/Hermitian)\ **Post date:** [July 10, 2013, 3:07pm UTC](https://boards.straightdope.com/t/meaning-of-solid-line-on-the-road/663109/23 "2013-07-10T15:07:41Z")
> [@CookingWithGas](#): > > Where? I have driven the entire Beltway and have not seen this, unless you are thinking about where the new HOT lanes merge into the main lanes northbound just past the Dulles Toll Road. I take that to be more like a double line on the express lane and a double line on the main lane and they just kind of merge, rather than being a true quad. Yes, its involved with the new HOT lanes. Judging from Google Earth, one section looks like it is 3000 ft long. ---
**Author:** ![Kent\_Clark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kent_clark/32/105_2.png) [@Kent\_Clark](https://boards.straightdope.com/u/Kent_Clark)\ **Post date:** [July 10, 2013, 3:57pm UTC](https://boards.straightdope.com/t/meaning-of-solid-line-on-the-road/663109/24 "2013-07-10T15:57:07Z")
The I-70/I-270 junction in St. Louis was infamous for people cutting in and out of the exit lanes. They finally painted a 2-mile long double-white line, posted “Do Not Cross” signs all through it, and actually ticket drivers who violate it. ---
**Author:** ![Colophon](https://avatars.discourse-cdn.com/v4/letter/c/f05b48/32.png) [@Colophon](https://boards.straightdope.com/u/Colophon)\ **Post date:** [July 10, 2013, 5:11pm UTC](https://boards.straightdope.com/t/meaning-of-solid-line-on-the-road/663109/25 "2013-07-10T17:11:54Z")
> [@pulykamell](#): > > Maybe not a two-lane country road, but often large highways will diverge around natural obstacles, so where you had two lanes in each direction across a four-lane road, it splits off into two lanes into two roads, quite often not visible from each other (like when there is a wood in between), before meeting up again some ways down the road. If you’re not familiar with the area and merge onto such a highway, you can sometimes be confused as to whether you’re on a two lane highway with one lane in each direction, or on a two-lane highway with both going the same way. > > I know that I’ve been on roads where I asked myself, “shit, is this one-way or two-way?” Exactly. You’ve just joined [this road](https://maps.google.co.uk/?ll=51.023912,-2.660177&spn=0.003489,0.008057&t=h&z=17&layer=c&cbll=51.023912,-2.660177&panoid=q1o_kclsQ3pF6IG5aMIRQQ&cbp=12,78.81,,0,16.54). Quick, is it one way or two-way? How about [now](https://maps.google.co.uk/?ll=51.107833,-2.168126&spn=0.01393,0.032229&t=h&z=15&layer=c&cbll=51.107508,-2.167903&panoid=_RYy_ewH9WVCUB9guvElqQ&cbp=12,145.01,,0,21.81)? Actually, on the two-way stretches of this road, they often use cross-hatching to mark a centre divider, like [this](https://maps.google.co.uk/?ll=51.172943,-1.852881&spn=0.001739,0.004029&t=h&z=18&layer=c&cbll=51.173004,-1.852454&panoid=9dEWMnV8IZKdTQmZsXN1vg&cbp=12,264.04,,0,6.35), which helps. ---
**Author:** ![Blakeyrat](https://avatars.discourse-cdn.com/v4/letter/b/ecd19e/32.png) [@Blakeyrat](https://boards.straightdope.com/u/Blakeyrat)\ **Post date:** [July 10, 2013, 5:33pm UTC](https://boards.straightdope.com/t/meaning-of-solid-line-on-the-road/663109/26 "2013-07-10T17:33:01Z")
To summarize: - Dashed line: passing is permitted - Solid single line: passing is discouraged - Solid double line: passing is prohibited - White line: by convention divides lanes going in the same direction - Yellow line: by convention divides lands going in opposite directions That seems to jive with what I see on roads here in Washington State. The white/yellow convention is so strongly followed that I’d expect a road that didn’t follow it would confuse most drivers around here. ---
**Author:** ![newme](https://avatars.discourse-cdn.com/v4/letter/n/e0b2c6/32.png) [@newme](https://boards.straightdope.com/u/newme)\ **Post date:** [July 10, 2013, 6:22pm UTC](https://boards.straightdope.com/t/meaning-of-solid-line-on-the-road/663109/27 "2013-07-10T18:22:06Z")
> [@](#): > > Originally Posted by **excavating (for a mind)** … a bit unnerving when you’re going down a country road with a broken white line and you see a car coming at you (in the opposite lane). > [@Keeve](#): > > But it unnerves you, and I’m trying to figure out why. I think the broken white line has something to so with it. From the various posts above, there are different interpretations of what a broken white line might mean, such as “it’s okay to pass the car in front, if absolutely necessary”, or “drive in whichever lane you prefer”. I’m guessing is that you are unnerved because you didn’t realize that you need to stay out of the other lane. I’m guessing that this lack of realization is because you were relying on the brokenness of the line, but why would you think that?\*\* Dd you expect this to be a one-way road?\*\* > . Yes, since a white center line, broken or unbroken, \* always\* means one-way traffic in the US. It’s as if every white dash you pass is saying to you,“One-way, one-way, one-way.” ---
**Author:** ![Senegoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/senegoid/32/6606_2.png) [@Senegoid](https://boards.straightdope.com/u/Senegoid)\ **Post date:** [July 10, 2013, 7:33pm UTC](https://boards.straightdope.com/t/meaning-of-solid-line-on-the-road/663109/28 "2013-07-10T19:33:20Z")
Extensive [article on lane and curb markings](http://epg.modot.org/index.php?title=620.2_pavement_and_curb_markings_%28mutcd_chapter_3b%29) – With a great many illustrations. ---
**Author:** ![Keeve](https://avatars.discourse-cdn.com/v4/letter/k/f07891/32.png) [@Keeve](https://boards.straightdope.com/u/Keeve)\ **Post date:** [July 10, 2013, 8:47pm UTC](https://boards.straightdope.com/t/meaning-of-solid-line-on-the-road/663109/29 "2013-07-10T20:47:39Z")
> [@newme](#): > > Yes, since a white center line, broken or unbroken, \* always\* means one-way traffic in the US. It’s as if every white dash you pass is saying to you,“One-way, one-way, one-way.” I’ve been browsing Google Streets, looking at the lines, and it seems that every two-way street I look at has a yellow line down the middle, and if it is a wide street, the lanes are separated by white lines. I really never noticed this before. I never realized there was a pattern to the color. I’ve never really needed to, actually: I tend to stick to the right side of the road (being on the western shore of the Atlantic) and if I was ever on a one-way section it was always so obvious that I never needed to rely on the color of the lines. It would never even occur to me to say, “There’s a white line down the middle; therefore I can drive on the left,” or “There’s a white line down the middle; therefore I must not go in the other direction.” If I’m on a one-way street, there is quite ample signage to tell me. Ignorance fought! Thank you! ---
**Author:** ![dstarfire](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dstarfire/32/5762_2.png) [@dstarfire](https://boards.straightdope.com/u/dstarfire)\ **Post date:** [July 10, 2013, 10:18pm UTC](https://boards.straightdope.com/t/meaning-of-solid-line-on-the-road/663109/30 "2013-07-10T22:18:11Z")
Generally, I see double white lines along a section of road where sight distance is reduced making it unsafe to cross into the other lane (presumably traveling in the opposite direction). Going into a curve in the road, I’ll usually see a sequence like this: solid line next to a dashed line, with the dashed line on the side travelling the opposite direction (since they’ve exited the curve and can now see what’s ahead) in the curve itself will be a double white line meaning nobody can see far enough ahead to safely cross Coming out of the curve it’ll be another solid/dashed combo, but with the dashes on my side (since I can see the road ahead, but folks travelling in the opposite direction can’t because of the curve) ---
**Author:** ![Lord\_Feldon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lord_feldon/32/341_2.png) [@Lord\_Feldon](https://boards.straightdope.com/u/Lord_Feldon)\ **Post date:** [July 11, 2013, 4:41am UTC](https://boards.straightdope.com/t/meaning-of-solid-line-on-the-road/663109/31 "2013-07-11T04:41:50Z")
> [@Keeve](#): > > I’ve been browsing Google Streets, looking at the lines, and it seems that every two-way street I look at has a yellow line down the middle, and if it is a wide street, the lanes are separated by white lines. I really never noticed this before. I never realized there was a pattern to the color. I’ve never really needed to, actually: I tend to stick to the right side of the road (being on the western shore of the Atlantic) and if I was ever on a one-way section it was always so obvious that I never needed to rely on the color of the lines. > > It would never even occur to me to say, “There’s a white line down the middle; therefore I can drive on the left,” or “There’s a white line down the middle; therefore I must not go in the other direction.” If I’m on a one-way street, there is quite ample signage to tell me. > > Ignorance fought! Thank you! Also, if there are lines marking the shoulder on a one-way road, the line on the left side of traffic should be yellow, just like it is on a two-way road. This is more common on things like freeways than it is on urban streets. ---
**Author:** ![Keeve](https://avatars.discourse-cdn.com/v4/letter/k/f07891/32.png) [@Keeve](https://boards.straightdope.com/u/Keeve)\ **Post date:** [July 11, 2013, 12:44pm UTC](https://boards.straightdope.com/t/meaning-of-solid-line-on-the-road/663109/32 "2013-07-11T12:44:55Z")
> [@Lord\_Feldon](#): > > Also, if there are lines marking the shoulder on a one-way road, the line on the left side of traffic should be yellow, just like it is on a two-way road. This is more common on things like freeways than it is on urban streets. Yep, I noticed this just a few minutes ago while driving to work. ---
**Author:** ![Doug\_K](https://avatars.discourse-cdn.com/v4/letter/d/b5ac83/32.png) [@Doug\_K](https://boards.straightdope.com/u/Doug_K)\ **Post date:** [July 11, 2013, 1:52pm UTC](https://boards.straightdope.com/t/meaning-of-solid-line-on-the-road/663109/33 "2013-07-11T13:52:52Z")
> [@newme](#): > > Yes, since a white center line, broken or unbroken, \* always\* means one-way traffic in the US. It’s as if every white dash you pass is saying to you,“One-way, one-way, one-way.” It hasn’t always been that way. When I was a kid [white was the standard color](https://en.wikipedia.org/wiki/Road_surface_marking#History) for dividing lines. > [@](#): > > By November 1954, 47 states had adopted white as their standard color for highway centerlines, with Oregon being the last holdout to use yellow.[3] In 1958, the U.S. Bureau of Public Roads adopted white as the standard color for the new interstate highway system. ---
**Author:** ![Kenm](https://avatars.discourse-cdn.com/v4/letter/k/bc79bd/32.png) [@Kenm](https://boards.straightdope.com/u/Kenm)\ **Post date:** [July 12, 2013, 5:29pm UTC](https://boards.straightdope.com/t/meaning-of-solid-line-on-the-road/663109/34 "2013-07-12T17:29:01Z")
A Mad Magazine cover had Alfred E. Newman painting an entire white highway black, leaving only the dotted centre line white. > [@Doug\_K](#): > > It hasn’t always been that way. When I was a kid [white was the standard color](https://en.wikipedia.org/wiki/Road_surface_marking#History) for dividing lines. And stop signs were [**yellow**](https://www.google.com/search?as_st=y&tbm=isch&as_q=old&as_epq=yellow+stop+signs&as_oq=&as_eq=&imgsz=&imgar=&imgc=&imgcolor=&imgtype=&cr=&as_sitesearch=&safe=images&as_filetype=&as_rights=&biw=1063&bih=603&sei=VDvgUfLMFqTuyQHfx4CwDA). In Canada, they were yellow and round, but I can’t find a pic. ---
**Author:** ![Jim\_B](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jim_b/32/4338_2.png) [@Jim\_B](https://boards.straightdope.com/u/Jim_B)\ **Post date:** [July 13, 2013, 8:43am UTC](https://boards.straightdope.com/t/meaning-of-solid-line-on-the-road/663109/35 "2013-07-13T08:43:58Z")
> [@Kenm](#): > > A Mad Magazine cover had Alfred E. Newman painting an entire white highway black, leaving only the dotted centre line white. > > And stop signs were [**yellow**](https://www.google.com/search?as_st=y&tbm=isch&as_q=old&as_epq=yellow+stop+signs&as_oq=&as_eq=&imgsz=&imgar=&imgc=&imgcolor=&imgtype=&cr=&as_sitesearch=&safe=images&as_filetype=&as_rights=&biw=1063&bih=603&sei=VDvgUfLMFqTuyQHfx4CwDA). In Canada, they were yellow and round, but I can’t find a pic. Also, **Yield** signs were yellow. This actually may have been a little before my time even. But when I was very small, they had one by my Grandmother’s house. Also, traffic light casings were _black_. Again, they were almost all switched over when I was a very small lad. But there was one by my house that stayed that way for a surprisingly long amount of time. Yeah, I guess they thought the black would make the colors in the light stand out more. Talk about a silly idea :p. :):)🙂 ---
**Author:** ![Lord\_Feldon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lord_feldon/32/341_2.png) [@Lord\_Feldon](https://boards.straightdope.com/u/Lord_Feldon)\ **Post date:** [July 13, 2013, 9:35am UTC](https://boards.straightdope.com/t/meaning-of-solid-line-on-the-road/663109/36 "2013-07-13T09:35:21Z")
> [@Jim\_B](#): > > Also, traffic light casings were _black_. They still are in some places. My city just replaced all of its yellow traffic lights hanging from wires with black traffic lights hanging from rigid arms. ---
**Author:** ![snailboy](https://avatars.discourse-cdn.com/v4/letter/s/97f17d/32.png) [@snailboy](https://boards.straightdope.com/u/snailboy)\ **Post date:** [July 13, 2013, 11:25am UTC](https://boards.straightdope.com/t/meaning-of-solid-line-on-the-road/663109/37 "2013-07-13T11:25:43Z")
In addition to the above, [here](https://maps.google.com/maps?hl=en&vpsrc=6&ie=UTF8&ll=32.862484,-96.855888&spn=0.00042,0.000544&t=h&z=21&layer=c&cbll=32.862406,-96.855863&panoid=URezw7FTBStk3aEnX78Prg&cbp=12,354.49,,0,1.31) is an example of double white lines in Dallas. It’s right at the entrance ramp to a street (not a freeway) and prohibits people from moving into or out of the right lane near where the ramp merges. You can also see just above the stop sign for the entrance ramp it says, “Do not cross double white line.” We also have solid white lines for about 50 feet before major intersections as you can see [here](https://maps.google.com/maps?hl=en&vpsrc=6&ie=UTF8&ll=32.880253,-96.856141&spn=0.000423,0.000544&t=h&z=21). They basically say that you shouldn’t cross them unless necessary, but I don’t think you can get ticketed for crossing them in any circumstance unlike the double lines. As for the need for the two colors of lines, there are plenty of undivided highways in rural parts of Texas that have stretches where it’s three lanes with a passing lane for just one direction of traffic. You can see the beginning of one [here](https://maps.google.com/maps?hl=en&vpsrc=6&ie=UTF8&ll=32.148502,-94.495164&spn=0.000598,0.001088&t=h&z=20). It makes it a lot more obvious which direction the middle lane is intended to go. [Previous page](https://boards.straightdope.com/t/meaning-of-solid-line-on-the-road/663109.md?page=1)