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
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" |
Route shield image assets have been made available for reuse in software projects:
The following renderers currently do not support route shields:
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