Key:surface

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Public-images-osm logo.svg surface
Transportation in Tanzania Traffic problems.JPG
Description
Describes the surface of a feature. Show/edit corresponding data item.
Group: properties
Used on these elements
may be used on nodesmay be used on waysmay be used on areas (and multipolygon relations)should not be used on relations (except multipolygon relations)
Documented values: 55
Useful combination
Status: de facto

The surface key is used to provide additional information about the physical surface of roads/footpaths and some other features, particularly regarding material composition and/or structure.

Originally concerned about the surface in relation to transport and sports and more commonly used on linear features, this key is now increasingly used with certain areas of type natural=*. Note, however, that the values of natural=* and surface=* must not be confused; e.g. natural=grassland vs surface=grass and natural=glacier vs surface=ice. For broader descriptions of surfaces see Landcover.

Values

Value Comment Photo Abundance

Paved

paved A feature that is predominantly paved; i.e., it is covered with paving stones, concrete or bitumen. This value gives general description; use a more precise value if possible. Paved mosaic.png
asphalt Short for asphalt concrete - mineral aggregate bound by asphalt. Many such features are tagged as paved without specifying exact surface. Surface asphalt.jpg
chipseal Less expensive alternative to asphalt concrete, using a thin base of hot bitumen or asphalt with aggregate pushed into it. Common in many American countries and Oceania. Often hard to distinguish from asphalt concrete by laypersons, some consider it as subtype of asphalt rather separate surface. In the end many chipsealed roads are tagged as asphalt instead. Chipnseal.jpg
concrete Portland cement concrete, forming a large surface, typically cast in place and may have predetermined breaking joints. For pre-fabricated plates, please use concrete:plates or concrete:lanes if you know how the concrete is laid out and one of these tags fits. Magallanes, ruta 9, 2.jpg
concrete:lanes Long, narrow concrete elements for a two-tracked vehicle (motorcars) so that the tires always hit the concrete. There might be sand, ground, grass, pavers, asphalt, etc. in between them. Note that if you tag a single-tracked way you just use concrete, since there are no lanes. Concrete lanes.png
concrete:plates Heavy duty concrete plates placed closely together. Might have tar, sand, or grass in between the connections. Bypass road made of big concrete plates.jpg
paving_stones A relatively smooth surface paved with artificial blocks (block pavers, bricks) or natural stones (specifically, flagstones), with a flat top. The gaps between individual paving stones are very narrow, either because the stones have a perfectly regular shape (rectangular, or any surface-filling shape) or because they have been carefully selected, fitted and placed in order to form an even, closed surface. Mix of paving stones IMG 20200910 163455.jpgSquare paving stones.jpgIndian sandstone paving slabs for patio garden.jpg
sett Sett paving, formed from natural stones cut to have roughly a flat top, with a regular or irregular shape. The stones do not cover the surface completely, unlike paving_stones. They also may be not entirely flat. Pflastersteine 1.jpgGranite Setts.jpg
unhewn_cobblestone Raw cobblestone of natural, uncut, rounded stones. Unlike pebblestone, the stones are firmly connected to the ground. Ancient road surface.jpg
cobblestone cobblestone is an unclear value, and was widely used for sett and actual cobblestone. Please adopt a more precise value, like sett or unhewn_cobblestone (described above).
cobblestone:flattened Should not be used, as there is neither a commonplace or defined meaning. Likely use sett or unhewn_cobblestone instead.
bricks A surface paved with dried clay bricks. Note that some people use surface=paving_stones for them and treat them as subtype of paving stones. Reformierter Schulgang (7) in Leer (2023).jpg


metal Used for metal-surfaced bridges, or for temporary tracks over fields for normal road vehicles or site traffic (note that objects lasting for just a few days should not be mapped in OSM). Tread chrome metal.jpgMetal footbridge over Sand Quarry - geograph.org.uk - 1325566.jpg
wood Used for wood surfaced bridges, plank walkways, and garden decking. Bridge-path-straight-wooden (24029070260).jpg
stepping_stones Stones or plates individually arranged in a row, allowing to walk on, surrounded by an unpaved medium such as grass or water Stepping stones - geograph.org.uk - 832601.jpgRiver Rothay stepping stones 120508w.jpg

)

rubber Playground safety surfacing made of recycled rubber tire products such as poured rubber, rubber tiles or loose rubber mulch. These surfaces are usually made of rubber designed specifically for aesthetics, child safety, and/or ADA wheelchair accessibility. Pärnu mänguväljak.IMG 20210807 134624
user_defined All commonly used values according to Taginfo.

Unpaved

unpaved A feature that is predominantly unsealed (unpaved); i.e., it has a loose covering ranging from compacted stone chippings to earth. Unpaved roads may, in aerial imagery, show evidence of water along their course; in such circumstances, the waterway should not be tagged as a stream, though it might appear as such. This value gives only a rough description; use a more precise value if possible.
compacted A mixture of larger (e.g., gravel) and smaller (e.g., sand) parts, compacted (e.g., with a roller), so the surface is more stable than loose gravel. Used, for example, for park paths, better tracks, some service ways, … Best sort of ways below paving with asphalt, concrete, paving stones. Sometimes known as water-bound macadam. Mixture and compacting leads to more grip and stability. Compacted forest track no1.jpg
fine_gravel This tag is used somewhat inconsistently; see its detail page. It may be used to specify fine loose gravel (as shown in the picture) which makes it unsuitable for kick scooters and bicycles without fat tires (e.g. when loose fine gravel is just put on top of soil), but it is also sometimes used as an alias for compacted (e.g. multilayer pavement with a stone or gravel basis and a topmost surface of firm, granular grit, basalt or quartz, as invented by the Roman empire, which is easy to cycle on, and motorized vehicles will not move stones, nor will bicycles tires leave any imprints on it). If the gravel is fixed instead of loose, please consider using well-defined compacted instead. Fine gravel path in Voltino, Zagreb


gravel This tag has very large meaning range. Used for cases ranging from huge gravel pieces like track ballast used as surface, through small pieces of gravel to compacted surface. Štěrková cesta u Pláštíku.jpg
shells Describes the surface of a feature as covered in small (parts of) seashells; commonly seen on footways and cycleways in the Netherlands.
rock Big pieces of rock used to improve path quality or exposed bare rock, including trails across natural=bare_rock. Typically in mountainous areas. Cascade canyon trail teton 20190713 095423 1.jpgTrail in Tatra mountains paved with local rocks.jpg
pebblestone Pebbles are stones rounded by waves or river flow. Typical size range from 2 to 8 cm. Describing a surface in OSM they are loosely arranged. Like gravel pebbles can be used as a building part of compacted. Dscf1781-800.jpgDscf1829-800.jpgDscf1831-800.jpg
ground No special surface, the ground itself has marks of human or animal usage. This value gives only a rough description; if possible, use a more precise value such as grass, clay, sand, earth, gravel or pebblestone. Gfp-florida-big-shaols-state-park-forest-trail.jpg
dirt Used for where surface is exposed earth, soil, or dirt, but it is not sand, gravel, or rock. Gravel is sometimes mistakenly called dirt. Some compacted surfaces are sometimes called "dirt" too, please consider the definition of compacted. Rainy dirt road on the Tibetan Plateau.jpg
earth Used for where surface is exposed earth/soil/dirt but it is not sand or gravel or rock. The same meaning as dirt. Rainy dirt road on the Tibetan Plateau.jpg
grass Grass covered ground. Mostly nice to walk. May turn into surface=dirt or become overgrown and disappear. Grass path on field 20160719.jpg
grass_paver A sort of permeable paving using regular cell structure, where the voids in this structure enable rainwater to drain into the ground and the structure itself increases the load bearing capability. Often used for parking lots or infrequent used ways like for emergency-vehicles. Dscf1611-800.jpgDscf1614-800.jpg
metal_grid Metal grids are often used as a surface on industrial-style bridges or stairs. When wet, the surface can become very slippery, especially for bikes. The surface can also be unsuitable for dogs, due to the sharp edges and the look-through effect. This surface is sometimes known as metal grate, metal grating, steel grate/grating, or open grate. Detern - Arnold-Goudschaal-Weg - Schöpfwerk Holte 08 ies.jpg
mud Similar to ground but most of the year wet which gives a soft ground with low carrying capacity. Mostly found on wetland like swamps or in tidal areas. Sometimes also found on slopes draining onto a way. Muddy Path - geograph.org.uk - 3017448.jpg
sand Small to very small fractions (less than 2 mm) of rock. Sand Way.jpg
woodchips Woodchips as a surface, perhaps for a playground or walking trail. Can consist of either chips of actual wood, or of bark only. Sometimes written as wood chips. Tanner Moor 2 (DFdB).jpg
snow Winter roads surfaced with compacted snow.
ice Ice roads, winter roads Jaatee2003.jpg
salt Dry salt lakes 2012.10.02.155200 Bonneville Salt Flats Utah.jpg
user_defined All commonly used values according to Taginfo.

Special (sports, etc.)

clay Most common on tennis courts. Sometimes used for other sports: soccer, athletic tracks, boules, etc. EVD-tenis-212.jpg
tartan A synthetic, all-weather surface typically used in running and other sport tracks. Although Tartan is a trademark, it is used as a generic term due to its widespread usage. Athletics track.jpg
artificial_turf An all-weather surface made from synthetic fibres to look and feel like natural grass. Often used for tracks and pitches of sports such as football, baseball, etc. Kunstgress.JPG
acrylic An artificial surface covered with acrylic resin-bound coating. Often used for tennis courts, basketball courts, etc. Prominent brands include: DecoTurf, GreenSet and so on. Court Arthur Ashe.jpg
carpet Carpet may be used for some sport courts such as indoor tennis courts and appear on some highway=corridor. Korty power game.jpg
user_defined All commonly used values according to Taginfo.

This table is a wiki template with a default description in English. Editable here.

Surface for motor roads

True cobblestone best tagged as surface=unhewn_cobblestone - more specific than surface=paved for this surface

For roads for motor vehicles, there is typically an assumption that the surface is surface=paved unless otherwise stated. Paved in OpenStreetMap is non-specific and may cover sealed, tarmac, asphalt, bitumen, even sett or true cobblestone. surface=unpaved is treated as the opposite of paved. More specific tags can be used for surfaces which are normally classified into paved or unpaved for routing purposes. Navigation software should assume that roads-that-are-not-paved will have slower driving speed (and therefore longer driving time) and may be impassable in some weather conditions.

On paved roads, tags more specific than surface=paved are also welcomed; for example surface=asphalt.

smoothness=* is also an important surface property and refers to surface regularity/flatness, regardless of material. May be especially useful for roller blades and similar purposes.

tracktype=* is also an important surface property and refers to surface firmness, regardless of shape.

highway=* ways should ideally always be tagged with surface (and/or with tracktype=*) given that there is no default for such paths.

Rendering software convention varies, but generally roads-that-are-not-paved are shown in a different colour but same width as their paved cousins or use the same colour but are dashed. Rendering of road surface in standard OSM style is a complicated subject.

In some cases when other tags are not sufficient to describe the road conditions good enough the use of smoothness=* and maxspeed:practical=* can be considered. maxspeed:practical=* can be useful in situations where other tags are not sufficient to describe what kind of travelling speed could be reasonably expected. If there is one good surface=unpaved road, where practical speed is 60 km/h, and a second bad road with concrete:lanes surface allowing a practical speed 10 km/h, users or routing software could be misguided to choose the second road for routing, because by default paved roads are assumed to allow much higher speeds than unpaved roads.

Surface for footways and cycleways

If tagged as one way with segregated combined cycleway+footway as one way that requires cycleway:surface=asphalt and footway:surface=paving_stones for specifying surface

If a footway or cycleway was tagged as a tag (not as a separate way) on a highway (i.e., highway=secondary + cycleway=track/lane), you can add surface by the following syntax:

sidewalk:surface=*

or more specific

sidewalk:both:surface=*
sidewalk:left:surface=* (left side depends on way direction)
sidewalk:right:surface=* (right side depends on way direction)

Or if there is a foot- or cycleway only at one side from street, or there are different surfaces at both sides, you can use right and left (or both, to tag explicit both sides):

cycleway:right:surface=asphalt
cycleway:left:surface=paving_stones

See cycleway:right=* / cycleway:left=* / cycleway:both=* for more examples.

With this syntax you also can add other relevant tags like: smoothness=*, oneway=*, bicycle=*, foot=*, width=*, segregated=*, and more.

In case of segregated cycleway+footway tagged as a single line where each has a separate value, footway:surface=* + cycleway:surface=* can be used.

Default values

There are no default values for surface, it is generally considered as OK and desirable to tag it explicitly for all roads. In case of missing surface=* data consumers may sometimes successfully guess values based on location of object and values of highway=*, lit=*, tracktype=*, tiger:reviewed=no and other tags[1][2][3]. Only in some cases, like on highway=motorway, it can be assumed that all of them will be paved.

Data consumers may also treat untagged surface specially (for example display "no data" in surface statistics listing).

Note that in some areas assuming that paved surface is default may be dangerous.

Uses

The primary use is navigation. A router for bicycles could avoid an otherwise normal road that is tagged as having surface=sand. For vehicles, the router might tie-break by preferring a slightly longer asphalt route over a earth/compacted/gravel/cobblestone route. Pedestrians probably also prefer any paved value over a potentially muddy footpath. The tag can furthermore be used to use the right texture when rendering, for example to indicate which ways are unpaved.

OsmAnd shows smoothness and surface, if enabled in the menu (Configure map - Details). Here is the map key with the rendering for each smoothness and surface value.

Potentially helpful tools

See also

Maps showing surface data

References

  1. https://lists.openstreetmap.org/pipermail/tagging/2019-September/048330.html
  2. https://lists.openstreetmap.org/pipermail/tagging/2019-September/048338.html
  3. https://lists.openstreetmap.org/pipermail/tagging/2019-September/048355.html "Ultimately, where information is missing, you as a data consumer will need to make a decision about whether or not a road is likely to be paved or not. Adding a default (even per-country) won't magically make all non-surface-tagged roads paved or unpaved"