United States/Road signs

Part of United States mapping project.

Standard signs

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.

Refer to the MUTCD field guide for the standard code for an unfamiliar road sign you see in street-level imagery, as well as suggestions on how to tag the infrastructure, advisory, or regulation that it indicates.

Route shields

Route shields figure prominently in the U.S. driving experience.

In the U.S., motorists navigate long distances using a panoply of official but decentralized route marking schemes, or networks (network=*). Routes and their markers, or route shields, are designated by a variety of state and local transportation agencies and toll road operators. Route shields usually bear an unprefixed route number (ref=*) inscribed within a symbol. Unlike other kinds of road signs, route shields assume the motorist recognizes each symbol and is aware of the differences between each network. Networks often have conflicting numbering schemes, so it is important for software to identify routes using accurate symbols instead of making generalizations.

The most well-known shields belong to the following networks:

• Interstate highways
• U.S. Routes
• State highways, routes, or roads

In addition, some states have multiple state route networks, county route networks in every county, or an extensive network of toll roads with special shields. If you encounter an unfamiliar shield in street-level imagery, consult the route shield field guide to determine the correct tags for the relevant ways and relation.

Traditionally, road atlases and online maps have relied on generic shields to simplify the user experience: for example, a state route always looks like and a county route always looks like . However, these generalizations can be counterproductive depending on the use case.

Route shields are typically accompanied by a cardinal direction indicating which of the route's termini one side of the road leads toward. The cardinal direction is indicated by navigation software but not by rendered maps.

Implementations

Renderer	Debuted	Relations	Concurrencies	Recognizable shields					Notes
				Interstates	U.S. Routes	State	County	Others
Amazon Location Service from Open Data	2023	?	?	yes	yes	Generic	?	N/A	[1]
GNOME Maps	2024	yes	yes	yes	yes	yes	yes	Various toll roads, tourist routes	Based on OpenStreetMap Americana
Magic Earth	?	?	yes	yes	yes	no	no	N/A
Mapbox Standard	2023	no	Only within a network	yes	yes	yes	no	N/A
Mapbox Streets	2015	no	Only within a network	yes	yes	Generic	no	N/A
Mapbox Leaflet	2014	no	no	yes	yes	Generic	no	N/A
Mapbox Navigation SDK	2017	N/A	yes	yes	yes	yes	Generic	N/A	Displays shields in UI based on destination:ref=*
MapQuest Open	2010	no	yes	yes	yes	yes	no	N/A	Discontinued in 2015
MAPS.ME	2017	yes	yes	yes	yes	no	no	N/A
Mapzen house styles[2]	2016	no	no	yes	yes	yes	no	N/A
OpenStreetMap Americana	2022	yes	yes	yes	yes	yes	yes	Various toll roads, tourist routes	Lays out concurrencies of up to six routes along the road
Organic Maps	2021	yes	yes	yes	yes	no	no	N/A
OsmAnd	2016	yes	yes	yes	yes	yes	Generic	N/A	Combines relation-based shields with way-based shields
osm-shields (Phil Gold)	2012	yes	yes	yes	yes	yes	partial	Various toll roads, townships	Hosted by OSMUS from 2013 to 2021; prerenders combinations of shields in multiple orientations; see Wayback Machine, SotMUS 2013 talk
osm-shields (Kevin Kenny)	2018	yes	yes	yes	yes	yes	partial	Various toll roads, townships	Forked with more solid technical foundation; clusters concurrencies in a grid to avoid prerendering
Overlay by Richard Weait	2010	yes	partial	yes	yes	yes	?	Historic 66	Transparent overlay atop openstreetmap-carto; see SotM 2011 talk
Radar Maps Platform	2023	no	no	yes	yes	Generic	no	no
Stamen Terrain	2011	yes	no	yes	yes	CA only	no	N/A	Optimizes shield positioning using Skeletron
TopOSM	2009	no	no	yes	yes	MA only	no	N/A
TracesMap	2022	no	no	yes	yes	Generic	no	N/A	Ignores modifiers like "Business"

An Indianapolis route concurrency in the original osm-shields.

Route shield image assets have been made available for reuse in software projects:

• Rebusurance

The following renderers currently do not support route shields:

• openstreetmap-carto [3][4]

Bike Routes

Main article: Cycle routes#United States

See also

• United States roads tagging/Routes, a guide to tagging routes based on shields
• United States roads tagging
• United States Road Classification
• Dynamic Sophox map of MUTCD traffic signs by series and color