United States/Road signs

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Flag of United States Part of United States mapping project.

Sign codes

MUTCD adoption by state

The traffic_sign=* tag is optionally set to an ISO 3166 country code followed by a specific sign code. The source for most sign codes in the U.S. is the Federal Highway Administration's Manual on Uniform Traffic Control Devices (MUTCD). The designs are detailed in a separate document, Standard Highway Signs and Markings (SHSD).

Unlike in other countries, the national standard is not mandatory nationwide. Several states substitute their own state-level MUTCD standards; many other states supplement the MUTCD with state standards. Regardless, in a given state, most sign codes match the national standard. State-specific sign codes represent at most a small fraction of the signs in a given state.

Highway route shields

Highway driving in the US is a way of life and features prominently in film and television. The highway system delivers all manner of goods to Americans from food to building materials and from lubricants to pet rocks.

The highway shields for the Interstate system and US Route system are iconic to US drivers. A glimpse of the familiar blue and red Interstate shield provides context to the situation immediately. Will this next scene in the film include a dramatic highway chase? Do the parents face a long drive with their caterwauling children?

The shields are even more useful for navigation. It is their ubiquity and recognizability that returns lost drivers to their intended routes. They allow reasonable assumptions of road quality when changing plans due to traffic, weather alerts or construction.

Wouldn't it be nice if OSM maps of the US could have the familiar highway signs, used appropriately?


TopOSM was perhaps the first OpenStreetMap-based map to use U.S.-specific shields. It used the MUTCD-standard Interstate and U.S. route shields and a square marker for state routes. Similarly, MapQuest Open displays state routes as rounded rectangles. Stamen Design's Terrain map additionally features California state highway shields. It uses Skeletron to optimize marker positioning.

In 2010, Richard Weait developed a crude overlay displaying reassurance-style markers for some U.S. state and Canadian provincial routes. At SotM 2011, he discussed future work to reliably mark concurrencies, an area in which commercial maps also fall short.

In 2012, Phil! Gold incorporated these ideas into an experimental rendering that marks each Interstate, U.S., and state highway route relation with cutout-style shields. Unlike other online maps, this map uses state-specific shields and even handles many one-off parkways, such as the Pennsylvania Turnpike. The map is implemented as an overlay atop OpenStreetMap's standard Mapnik stylesheet. See the talk-us thread for details and Launchpad for the source. In 2013, it was added to openstreetmap.us.

There is an open request to implement similar functionality in the Standard map style at osm.org.

Rebusurance is a suite of scalable image assets that can be used for displaying U.S.-style route shields on a map.

Interstate Highway System

The US Interstate Highway System is well-described on Wikipedia. International OSM contributors are encouraged to read the Wikipedia article.


The Interstate shield two widths and several variations. As always Wikipedia knows all and many specific shield can be seen there.

Perhaps OSM can allow tagging to include these shield in US maps?

US Interstate tagging

Use the talk section of this page to suggest how this should be tagged.

US Highway System

The US Highway system predates the Interstate system. It is ably described at Wikipedia. US numbered highways or "US Routes" may be surface streets or motorways.


More shields and variants can be found at Wikimedia

California variant


Bannered variants

Banners route shields include Truck, Alternate, Business, Bypass, City, Spur, and others.


State highway systems

All states in the US also have a state highway system which consists of hundreds of state-maintained roads that don't fall into the Interstate or U.S. Route systems. State highways can have bannered variants like U.S. highways above. The federal MUTCD suggests using a circular shield with a black background for state highways; however, the states are free to come up with any design they desire. Delaware, Iowa, Kentucky, Mississippi, and New Jersey use the circular highway shield. (Oklahoma did the same until 2006.) Vermont uses the circular shield for segments of state routes that are maintained by the encompassing town. Virginia uses the circular shield for secondary state highways, and West Virginia uses it for county roads. The other states use custom designs. A gallery of the state highway shields in use is available on Wikipedia.

Ideally we would be able to use these shields in maps (Wikipedia usually does this), but as there are 47 different designs doing so is liable to be quite inefficient. Also, some shields are slightly impractical at the small sizes required by maps. Most maps in the US use the circle for state highways even in states which do not use these on roadside signs.

In addition, some states (Tennessee, Texas, Missouri, Montana, Virginia) have a secondary state highway system which uses different shields. Texas actually has several secondary systems, including Farm-To-Market Roads (FM), Ranch-To-Market Roads (RM), Ranch Roads (RR), Park Roads (PR), Beltways, and of course several of these have bannered variants. There's also a unique "NASA Road 1" in Houston which is state maintained. Missouri's secondary system is well-known because it uses one- and two-letter designations (which sometimes leads to eyebrow-raising junctions when letters that spell out words happen to intersect). These designations are not quite as standardized on road maps but often a plain white square is used.

Legal issues

We need to know if we may legally include the shield designs in OSM. I'm uncertain what the answer is from a quick, layman's reading of the materials. On the "Go ahead" side of the argument, publications of the US Government are paid for by taxpayers and released to public domain. Also in favour of OSM use, the road signs must be built to published standards Wikipedia:Manual on Uniform Traffic Control Devices. On the other hand a Wikipedia article suggested that the governing body AASHTO claims copyright on the interstate shield design, and it is a registered Trademark (Registration 835,635).

But the shield is commonly used on many maps, and the purpose of the trademark is to prevent confusing usage on commercial signs. It "has been used several times over the years to prevent or remove Interstate-like signs near the Interstate highways, where they might confuse the traveling public and cause accidents."

are we talking about trademark or copyright? I think the difference between the two would allow it's use in map products, but not on signs where people would think it indicates a highway. --Korea 14:17, 15 August 2007 (BST)
Correct. The design is trademarked, not necessarily copyrighted. If I understand correctly, there should be no legal encumbrance to mapmakers' use of the Interstate shield for identification of Interstate highways. This is supported by the fact that absolutely every U.S. road map, without significant exception, uses the Interstate shield to mark Interstate highways. If they had to license it from AASHTO, I'm almost sure that its use would not be so widespread on maps. --Marnen 04:38, 3 July 2008 (UTC)


Not an issue. A trademark may always be used truthfully.


A trademarked graphic may also be copyrighted, if it has sufficient creativity. This is often claimed because of the difficulty and expense of securing trademark registration for the graphic. By asserting copyright, and then licensing the use of the graphic in the same manner as a trademark, such protection may be garnered. It's not clear how much creativity there can be in a shield, given that a shield has a given shape. Choice of colors? But the USA's flag's colors are red, white, and blue.

The U.S. Highway shield was introduced in 1926, and the shape's usage as a federal symbol predates 1923, so the possibility of copyright has expired. The Interstate shield comes from the late 1950s, and, due to U.S. copyright laws of that time, would have had to be registered at the time and later renewed if a copyright was claimed. A search of http://comminfo.rutgers.edu/~lesk/copyrenew.html for American Association of State Highway Officials turns up nothing relevant, and all the evidence elsewhere is that it's only trademarked[1][2], not copyrighted.
As for individual states, the typical fallback for maps (actually used by some states on signs) is a circle. --NE2 10:46, 13 December 2009 (UTC)
Furthermore, many states simply use the state's outline for their shields: such shapes are ineligible for copyright. – Minh Nguyễn (talk, contribs) 21:55, 13 December 2009 (UTC)

Bike Routes

Main article: Cycle routes#United States

See also