History of double solid yellow line

When did the standard lines on roads come into use? That is, the double solid yellow line, dashed yellow line, etc. And are they used the world over? If not, which countries use (or don’t use) them?


…they have a Wikipedia article for that?

They aren’t used here in Israel - we have single solid white lines and single dashed white lines. Yellow means bus lanes.

It’s the same in Germany. Yellow is only used for temporary markings during road work.

This thrilling document (“The Evolution of the US Pavement Marking System”) tells how it changed in the Federal guidelines: https://ceprofs.civil.tamu.edu/ghawkins/MUTCD-History_files/MarkingColorEvolution.pdf

I believe it says that yellow center lines became “recommended” in the 1948 revision of the standards. Before that, different localities had their choice of using a handful of colors. After 1978 yellow became the “required” color.

I don’t really have a cite for this, but a government teacher of mine said that forcing uniformity with road marking colors was one of the first uses of block grants, where federal funding is used to force states to comply with certain rules or pass certain laws. A lot of the snowy states didn’t want to go along with the requirements that the shoulder markings be white because they become invisible in even light snow, but the feds made them a requirement of getting highway funding. Of course since it’s been used to raise drinking ages, push tougher DUI laws, etc.

There is place outside Marquette, MI (on now county road 492) that claims the hiway centerline invented there in 1917, but that obviously might not be true.


New South Wales used to have an unbroken yellow line (sometimes double lines), which meant crossing or passing was prohibited. The broken white lines allowed passing and crossing and just divided lanes and/or the middle of the road.

I’m not sure when it happened, but some boffin decided that we should have both types of lines painted white. I actually prefer the yellow/white combination because I felt the yellow stood out more and the ‘no crossing this line’ rule was more obvious.

Solid white in the US also means don’t cross. When it’s yellow, it just means that the traffic on the other side of the line is going in the oposite direction.

A lot of people do cross the solid white in the US. They are often used for demarking turn lanes.

You could just check first. Every single time.

This is factually incorrect. In California, the vehicle code states that double lines may not be crossed, regardless of their color.

Generally speaking, white is guidance while yellow is mandatory.

The rare instance of a single white line that may not be crossed will come with a caveat: a sign will prohibit crossing of that line. If detained for an infraction, you will be cited for failure to obey the sign.

I did. I looked up “double solid yellow line” and it wasn’t there.

Anyway, I’m surprised the erudites here suggest we rely so heavily on a website with well-chronicled…issues.

Putting double yellow line into the Wikipedia search box gives the link that Duckster found. So I flat out don’t believe you. Not only that but the first hit on Google for double yellow line is that Wikipedia page. You didn’t check anything before posting and now you’re pretending you did. I’m not buying it.

Wikipedia is solid for basic facts, like dates, which is all this question calls for. You can’t depend on it for interpretations of facts, and anyone doing a serious project would want to doublecheck the source material, true, but people should use Wikipedia as a source for facts and only then ask for more info if that isn’t sufficient. It’s also good because people post on it from all over the world, so the info is not limited to the U.S.

Yes, for all values of “that”.

In the US, yellow lines should be on your left. if they are not, you are driving on the wrong side of the road.

Here in Ontario, we’ve started using orange for temporary markings. On public roads, yellow separates traffic going in different directions, while white separates traffic going in the same direction. White is also used for in-lane markings. On private property, such as mall parking lots, the markings are often all yellow.

Try again.

In Minnesota there exist double white lines and single white lines. Double white lines may not be crossed (and there is usually a sign informing you of the fact). Single white lines are an attempt to discourage you from crossing, but are in fact legal to cross. A good example of the former is to seperate the toll lanes on freeways from the regular lanes at certain locations, the latter is through the Lowry Hill Tunnel. People routinely ignore the double white line rule, and other people will not cross a single white line even when safe to do so.

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Please note that the post you are quoting only noted a “solid” line, not “double solid” lines.

The distinction made was that yellow indicated oncoming traffic, a point that I believe is accurate.

Solid white lines are not to be crossed, usually under penalty of a citation, (at the discretion of the cop watching it happen), but the color indicates direction of traffic.
In construction zones on freeways, the lane lines are often made solid at about the point where a sign is erected warning motorists to not change lanes, but those lines are single and white.

There are also many places where there are two sets of lines, one solid and one broken, that indicate that the person in the lane with a solid line must not cross it while the person going the opposite direction may cross it to pass. (This will occur on a hill where the solid line is for the lane going up the blind side and the broken line is on the lane going down with no obstructed vision.
However, those lines, solid or dashed, are yellow to indicate oncoming traffic.

agree that the solid white line (USA) is not to be crossed, the double line gives directions for that lane, color indicates traffic direction in that other lane.

the solid white line also is at entrance/exit lanes or turning lanes where changing at that point would be a hazard because it is too early or too late to do so. edge of road is also indicated by a solid white line.

don’t know history.