United States roads tagging
There is conflicting information on this topic at several places. Please see Talk:Highway tag usage and the Talk-US Mailing List for discussion.
Contents |
Interstates
See detailed page on Interstates.
Motorway tag
highway=motorway applies to almost all Interstates, but a very small number of Interstates or segments of Interstates warrant a lower classification, such as highway=trunk. Any freeway anywhere in the United States, whether designated Interstate or otherwise, gets highway=motorway. Any ramps onto or from a motorway get highway=motorway_link.
Access onto a motorway comes exclusively through ramps (controlled access). A few private driveways and farm access roads emerge directly onto some officially designated Interstates in otherwise remote areas; even where these driveways lead into median breaks, they do not imperil motorway status. Most public roads that intersect a motorway or trunk highway through motorway links or trunk links get a designation no lower than highway=tertiary in all directions from the intersection.
Trunk tag
NOTE: The definition below is not commonly used; see the talk page. Many people use trunk to mean "expressway"-grade arterials with at-grade intersections, major non-motorway intercity highways, or both.
Most controlled-access highways without adequate speed or travel lanes or with obstructions should be designated highway=trunk. This designation applies, for example, to the two-lane Interstate 93 in northern New Hampshire. highway=trunk should apply to any segment, travel on which typically implies or necessitates clearing the obstruction. Any ramps onto or from a trunk highway get highway=trunk_link, even if they otherwise qualify for highway=motorway_link. Ramps leading into or from weigh stations, inspection booths, welcome centers, rest areas, and similar diversions accessible only from a trunk or motorway highway also carry highway=trunk_link.
Trunk highways include controlled-access highways that lie within military bases; contain draw bridges, toll booths, or other obstructions; have a speed limit less than 50 miles per hour; or have only one lane in each direction, whether divided or otherwise (sometimes called a "super-two" freeway). The designations highway=trunk and highway=trunk_link apply to all toll roads.
Primary tag
Green-signed interstate business routes, loops, spurs, and similar forks (and Interstate 180 in Wyoming) should be designated highway=primary unless they qualify for highway=trunk or highway=motorway. Access on primary highways may be uncontrolled; controlled-access segments of such highways merit highway=motorway (or occasionally highway=trunk) classification. When ramps link primary highways to highways of the same or lower classification, those links should be designated highway=primary_link, and those highways designated no lower than highway=tertiary. In no case should any Interstate highway receive any designation lower than highway=primary.
Examples
A typical one-route Interstate:
| key | value |
|---|---|
| ref | I 95 |
A one-route named Interstate:
| key | value |
|---|---|
| name | John Fitzgerald Kennedy Memorial Highway |
| ref | I 95 |
A two-route Interstate:
| key | value |
|---|---|
| ref | I 95; I 495 |
A two-route named Interstate:
| key | value |
|---|---|
| name | Capital Beltway |
| ref | I 95; I 495 |
U.S. Highways
If the route is named, said names should be included in the name tag. As with all Open Street Map data, separate them from the other values with semicolons.
The ref tag for U.S. Highways should be:
- "US {route designation} {modifier}", where:
- {route designation} is the same as that in the name tag.
- {modifier} is the route modifier, if any, as above.
If there are multiple U.S. Highway routes that share the same way, each of the designations should be in the ref tag. The order is insignificant, but for the sake of clarity, ascending numeric order is recommended.
Many U.S. highways are divided, multi-lane highways; like motorways, these
Motorway and Trunk tags
If any segment of a U.S. highway or any other road merits highway=motorway or highway=trunk according to the criteria heretofore described, it should be so designated.
Primary tag
Almost all other U.S. Highways get highway=primary. A primary highway generally provides the best route (excluding motorways) connecting adjacent cities or communities (generally urbanized areas or urban clusters under the United States Census Bureau) of population 10,000 or more. This connection generally describes the function of the U.S. highway network; however, some states (particularly California and New York) have few designated U.S. highways, and in some places, State highways or other roads perform this function. State, county, and other highways that provide the primary connection between adjacent cities may be promoted to highway=primary, especially if they do not intersect another highway=primary between the two adjacent cities. It is not appropriate to promote a road to primary solely because it connects a city with one or more suburbs of that city or interconnects suburbs of the same city with one another.
Even where U.S. Highways connect only smaller communities, they still merit highway=primary unless they clearly do not provide the primary non-motorway route between the communities that they connect. (One example of a non-primary U.S. Highway is a bit of US 56 in Kansas City, where a more direct route just to the south is better suited for through traffic.) A few major urban arterials also may merit highway=primary if and only if they provide a clearly better routing (higher speeds and fewer delays arising from traffic signals, stop signs, or other obstructions) than available urban arterials bearing highway=secondary. Any interchanges on a primary highway carry the highway=primary_link tag, unless they lead to highway=trunk or highway=motorway.
In some states, pedestrians and cyclists legally can travel along primary highways and on highways with lower classifications but not on motorways. The legality of such travel may vary based on state and local law; however, primary highways often carry heavy loads of high-speed traffic that may endanger the safety of pedestrians and cyclists. Unlike motorways, highways designated highway=primary, highway=secondary, and highway=tertiary may have traffic signals. Most highways with a traffic signal should be designated no lower than highway=tertiary on both sides of the traffic signal. Primary highways generally lack stop signs; however, stop signs may control major intersections in rural areas with low traffic volumes and occur rarely elsewhere.
Former and Alternate alignments
Alternate and business U.S. highways generally carry highway=primary; however, if the density, function, or condition of such highways clearly does not merit highway=primary, they may be demoted, generally to highway=secondary.
Some U.S. highways have been decommissioned over the years; states occasionally post "historic," "old," or "former" on signs and maps. If they continue to perform the function of U.S. highways based on the criteria previously specified, then they may retain highway=primary; these routes may continue to retain their previous number but a State highway official designation. Depending on their function, official designation, and condition, they may qualify as highway=secondary (especially if they have or retain a state highway designation) or more usually highway=tertiary. Some decommissioned U.S. highways may be so broken, disconnected, or degraded that they make long-distance travel on them obviously impractical or entirely impossible with most vehicles; these routes qualify for highway=unclassified (or even highway=track, especially if no longer paved).
States occasionally reroute U.S. and other primary and secondary highways to provide better travel conditions. Depending on its new function and condition, the former alignment may be designated highway=secondary, highway=tertiary, or highway=unclassified (especially dead ends). Unpaved roads use highway=track or get dropped entirely if barricaded, privatized, or completely impassable. A different designation may be appropriate.
Examples
A typical one-route U.S. Highway:
| key | value |
|---|---|
| ref | US 522 |
A one-route named U.S. Highway:
| key | value |
|---|---|
| name | Washington Boulevard |
| ref | US 1 |
A two-route U.S. Highway:
| key | value |
|---|---|
| ref | US 50; US 301 |
National Forest Service, Bureau of Indian Affairs, Power Administration, and Bureau of Land Management routes
These roads are found in National Forests, Indian reservations, power administration (Bonneville, Tennessee Valley, etc) and BLM lands. The TIGER import has incorrectly tagged most of these ways as highway=residential, with their reference in their name=, and ref= unset. BIA routes should use relations, as the reference frequently carries beyond a single road similar to US or State highways.
| key | value |
|---|---|
| highway | (required) service, track, or tertiary depending on importance and status. |
| name | (optional) Should equal the name of the road, if named. |
| ref | (required) Should equal NFD (number), BIA (number), BLM (number), etc., where the number is equal to the way's road number. |
State Highways
State highways should have a name tag, giving the street name, if any (e.g., "Elm Street"). This applies mostly where a state highway passes through an urban area.
State highways should have ref tags having as their values:
- US: (optional; few editors have chosen to use this designation)
- The two letter abbreviation for the state per the United States Postal Service's state abbreviation list, another abbreviation used by the state (such as SR for State Road), or no prefix. Different states may have different standards for which to use, and there is no current inter-state standard.
- A space.
- The designation of the highway, be it numeric, alphabetic, or a combination.
The name and ref tags should not contain:
- Cardinal direction designations (e.g., "N", "S", "E", "W") unless they are part of the official state designation.
Individual states
Please add your own state if you have information to add.
Texas
Texas has multiple 'types' of state highway - these include Loop, Spur, Farm-to-Market, and Ranch-to-Market, among many others. See the tables below for ref=*.
Frequent types
| type of road | ref= |
|---|---|
| |
TX 6 or SH 6 |
| |
Loop 12 |
| |
Spur 408 |
| |
FM 3075 |
| |
RM 2381 |
| |
Park 5 |
| |
R 10 |
One-road-only types
Certain roads have a special designation different from any other road in the state.
| type of road | ref= |
|---|---|
| |
NASA 1 |
| |
TX OSR |
| |
BW 8 |
| |
Ranch 1 |
Higher designations
If a state highway qualifies for highway=motorway, highway=trunk, or highway=primary based on the criteria discussed previously, then it should be so designated. Segments of state highways that join U.S. or Interstate highways generally should carry the primary or motorway designations, respectively, unless circumstances warrant a lower classification.
Secondary tag
Most state highways should carry highway=secondary. In rural areas, the secondary highway network connects towns and smaller communities to the outlying world. Secondary highways can provide access to higher-traffic local destinations, including some state and national parks, colleges and universities, military bases, major tourist attractions, airports, and facilities that employ several thousand or more people. Corporate driveways, however wide, should be designated highway=tertiary or highway=unclassified if accessed thorough traffic lights or links/ramps and publicly accessible but otherwise highway=service or dropped entirely.
Urban arterials with two or more lanes in each direction, generally with traffic signals but without stop signs, either a few miles or more in length or forming a network with other secondary, primary, trunk, and motorway highways, also usually qualify for highway=secondary. Arterial roads generally carry high traffic volume (near or more than 10,000 vehicles per day) near the highest speed generally allowed on surface streets (non-motorways) in the jurisdiction. A few urban arterials with significantly fewer interruptions at traffic signals and other obstructions and higher overall traffic speeds may be promoted to highway=primary; these highways can carry close to 100,000 vehicles per day.
A secondary road may exist as an arterial on a military base or within a military gate, where access is limited only or primarily to military personnel, their families, base employees, and similarly interested persons. Highways within military gates should carry highway=secondary and access=private (or perhaps some other access tag).
Any way that serves as a circumvention of a traffic light or stop and is intended for turning or exit from a secondary road gets the designation highway=secondary_link oneway=yes, unless it leads to a primary or trunk road or a motorway.
Demotions
If the physical or traffic condition of a state highway or other road otherwise eligible for highway=secondary is inappropriate for such designation, then it may be demoted. Secondary highways generally should be paved and passable by on-road vehicles year-round (except perhaps seasonal closures in remote areas subject to extreme snowfall). Dead-end state highways that do not lead to towns or other locations justifying secondary designations and state highways inappropriate for travel with significant traffic volumes also may be considered for demotion, perhaps to highway=tertiary or highway=unclassified.
Example
| key | value |
|---|---|
| name | Sycamore Street |
| ref | WI 123 (or US:WI 123) |
County Highways
These should be mostly highway=tertiary but will vary from state to state.
Oklahoma and other states generally may not number county roads. In Pennsylvania, these are quadrant routes and some other state-maintained highways (and occasionally bridges). In Texas, for example, farm-to-market roads or ranch roads constitute tertiary highways. Wisconsin and other states have networks of county highways. The Commonwealth of Virginia and other states number practically every road in the county. Open Street Map should carry those county highway tags, but that tag does not imply any tertiary highway status. Most paved roads in most counties should be labeled highway=unclassified (or highway=residential in urban neighborhoods).
Individual states
Please add your own state if you have information to add.
Oregon
County highways may or may not have a ref= tag depending on the county, rural counties are more likely to have refs than urban ones.
New Jersey
County highways in New Jersey are divided into two groups, the '500 Series Routes' and individually assigned county routes. 500 Series Routes are coordinated by the state but maintained solely by the individual counties they traverse (except in cases in which they may multiplex with a state-maintained highway); with few exceptions, these routes are meant to cover long distances as alternatives to state highways and are contained within multiple counties. County routes designated within the individual counties usually have three-digit numbers beginning with 6 (or 7 if numbers beginning with 6 are used up) (Monmouth County and Bergen County do not follow this convention); there routes, with some exceptions (in which the number is usually carried over), do not cross county lines. Generally 500-series county routes should be tagged 'primary', and 600-series routes that cross county lines or link significant communities can be designated 'secondary' or higher depending on their importance or build quality. See the New Jersey page for more information.
Ohio
Some (mostly rural) counties in Ohio sign their routes; others do not. Those that do use either the blue pentagonal shields or the white or green rectangular ones. For the most part, these routes should be tagged highway=tertiary. There are, of course, exceptions. See Ohio#Tagging suggestions for Ohio and Ohio#County routes for more information.
South Carolina
South Carolina uses three route numbering systems: Interstates, Primary Routes and Secondary Routes. The Secondary numbering system is unique within a county. The Secondary numbering system carries the county number followed by a unique number for that particular road. An example is S-40-100. This defines a secondary road in Richland County (40) with a road number of 100.
Virginia
Virginia state routes are grouped into two categories: primary system(statewide); secondary system(countywide). Primary state routes are generally numbered below 600 statewide. Secondary state routes are generally numbered 600 and above within each county. Exceptions to the secondary system numbering within a county include I-664, state route 785 and state route 895
West Virginia
County highways are signed with a fractional number. As an aside, do not simplify them into whole or mixed numbers!
Higher designations
If a county highway qualifies for a higher classification (for example, as highway=secondary because it serves as an urban arterial), it should be so designated.
Tertiary highways
The designation highway=tertiary generally includes the predominant minor roads in a county. This designation generally includes well-trafficked routes (generally at least 1,000 vehicles per day) in all areas, roads providing access to minor attractions or employers, and urban collector streets. Roads meriting highway=tertiary include most of those with a traffic signal, or to which any tertiary or higher classed road defer right of way (at a stop sign, traffic circle, or other traffic control device), and divided mostly low-speed roads in neighborhoods, industrial parks, or shopping centers that carry low-speed traffic.
If a state maintains (or its smaller jurisdictions maintain) a set or sets of county highways that do not include a majority of highways in each county, then those county highways are generally considered highway=tertiary.
Unclassified roads
Some states and counties number practically every road in the county. Most of these roads should be highway=unclassified, but those in urban neighborhoods should be highway=residential. Most unpaved roads belong in highway=track.
Example
| key | value |
|---|---|
| name | North Fond du Lac Avenue |
| ref | CH V (or CR V) |
Other Roads
Roads that do not qualify as tertiary roads should be tagged highway=unclassified, but those in urban residential areas instead get highway=residential. Unpaved roads, dirt track roads, forest development roads, jeep trails, and roads not passable by all vehicles merit highway=track instead.
Roads through parking lots (or campgrounds), alleys, corporate driveways, and other special roads generally intended for travel to a particular destination get highway=service.
Ways on which most motor vehicle traffic is either legally of physically prohibitive get highway=path, or a more specific tag as appropriate. This category includes roads that normally function as hiking trails because of barricades opened only occasionally or rarely.
Tagging with relations
Ideally routes in North America will be tagged as relations. See Relation:route for the technical details on how relations work for routes in general; the following tagging scheme has been proposed:
| Key | Value | Discussion |
|---|---|---|
| type | route | (required) This is a "route" relation (as opposed to other types of relations) |
| route | road | (required) This route is part of the roadway network for automobiles (as opposed to a bus route, hiking route, cycling route, etc.) |
| name | common name | (optional; required if no number) A name for the road if it has no number (e.g. New Jersey Turnpike), or a name that disambiguates in the editor (e.g. I 10 (FL) rather than a bunch of relations that show up as 10). Other variations of Key:name are also permissible. |
| network | network identifier | (required if part of a route system) The route network the route is part of. US:I = Interstate signed highway network US:US = US signed highway network US:xx = Primary state signed highway network for state with postal code xx US:xx:(yyy) = Other state/local signed highway networks (secondary networks = secondary e.g. US:TN:secondary, US:MO:secondary; county routes e.g. US:CA:county or US:CA:CR; US:TX:loop/spur/FM/RM/UR/park/recreation) Some relations have the modifier added to this, while others have them on the ref tag. |
| is_in:state=* | State Postal Code | xx = e.g. OH;KY for I-275 in Ohio/Kentucky. FL for I-275 in Florida. |
| ref | reference number | (required if network is specified) The specific route number in question; may be alphanumeric (e.g. I-35E would have a reference number of 35E). Some relations have the modifier added to this, while others have them on the network tag. |
| modifier | type | (optional) Some routes have a "tab" (officially a "banner") attached to the route number that distinguishes it from other, related routes. Usually the text of the attached tab should be used; common examples include "alternate", "business", "bypass", "spur", "temporary", "toll", "truck". |
| direction | direction | (optional) Divided highways (dual carriageways) may have two route relations, one in each direction. Usually the cardinal direction of the tab on the sign should be used; for example, northbound US 101 should be tagged north. Unusual directional tabs (e.g. inner, outer, or directions on the QEW in Canada) should be expressed in full. Note the signed direction may sometimes be the opposite of the true orientation of the route (part of westbound US 90 Business in New Orleans runs eastward; part of eastbound I-26 in Tennessee runs to the west); the signed direction should be tagged. |
| symbol | url | (optional) Should be the URL of a graphical representation of the route's symbol, ideally in SVG format. For example, Wikimedia includes symbols for many US, Mexican, and Canadian routes. |
| state | proposed | (optional) Indicates that the route has been proposed but is not yet built or signed. Such highways may also have modifier=future.
|
Other tags such as Key:wikipedia may also be appropriate and may be included.
Overlapping route example
A named route may not overlap precisely with a numbered route. In this case, separate relations for each route should be used.
For example, the Wikipedia:Ohio Turnpike crosses Ohio. About 3/4 of the route overlaps with Wikipedia:Interstate 80, about 1/2 of the route overlaps with I-90, and about 1/4 of the route is part of I-76, but none of the numbered routes coincides exactly with the Turnpike and all three exist in more than one state.
So, in this case there should be a relation for the Ohio Turnpike (name="Ohio Turnpike", symbol=http://upload.wikimedia.org/wikipedia/commons/f/f5/OhioTurnpike.svg), separate (but overlapping as appropriate) from the I-76, I-80, and I-90 relations which should be specified as e.g. (network=I, ref=76, symbol=http://upload.wikimedia.org/wikipedia/commons/a/ad/I-76.svg).
A short named route (e.g. "Main Street" through a small town) should not be a relation; instead, the underlying ways should just be tagged normally.
Exit Info
See detailed page on Exits.