Top-level tag

Top-level, primary or feature tags are those that define the nature of map features and therefore may be the sole tags that exist on a map element. All other tags are additional or secondary and describe additional properties of map features.

All standalone map elements are supposed to have at least one top-level tag. An element may have more than one top-level tag (for example, building=school and amenity=school on an area representing a school building), as long as it reasonably conforms with the one feature, one OSM element principle. The "standalone" map elements are:

Nodes which are not part of a way,
Ways which are not part of a relation,
All relations.

Standalone elements lacking a top-level tag do not necessarily constitute an error, but they are typically ignored by data consumers. Many quality assurance tools issue detect such elements and issue warnings.

List of top-level keys

As of 2025, there are 30 top-level keys identified on this page, listed in alphabetical order in the table below.

Key	Elements	Description
`aerialway=*`		Used for various forms of transport for passengers and goods that use wires, including cable-cars, chair-lifts and drag-lifts.
`aeroway=*`		For physical infrastructure used to support aircraft, air travel, spacecraft and space flight.
`amenity=*`		For describing useful and important facilities for visitors and residents.
`barrier=*`		A barrier is a physical structure which blocks or impedes movement. Show/edit corresponding data item.
`boundary=*`		Used to mark the borders of areas, mostly political, but possibly also of other administrative areas
`building=*`		To mark the area of a building, a man-made structure with a roof, standing more or less permanently in one place.
`building:part=*`		To mark the outline of a part of building that has properties distinct from other parts of the building.
`craft=*`		A place producing or processing customized goods
`education=*`		Describes various educational features
`emergency=*`		Describes various emergency services, facilities, amenities or the possibility of access for emergency services
`entrance=*`		Used to mark entry (or exit) points to buildings or other enclosed areas.
`geological=*`		Used to describe geological sites.
`healthcare=*`		A healthcare facility.
`highway=*`		Used for roads and road-related facilities.
`historic=*`		Used for describing various historic features.
`landuse=*`		Mainly used for describing the primary use of areas of land.
`leisure=*`		Features associated with leisure activities.
`man_made=*`		Artificial structures other than buildings.
`military=*`		Facilities used by military forces.
`natural=*`	}	Natural physical landscape features, including those modified or created by humans.
`office=*`		A place of business predominately providing services.
`piste:type=*`		Indicates the type of a winter sports piste. Is top-level, since often in summer there are no visible features along the piste.
`place=*`		Defines the center or outline of a named place.
`power=*`		Facilities for generation and distribution of electrical power.
`public_transport=*`		Public transport infrastructure.
`railway=*`		Used for railways and railway infrastructure.
`route=*`		A customary or regular line of passage or travel, often predetermined and publicized.
`shop=*`		A place selling retail products or offering services.
`telecom=*`		Main key for telecommunication systems and networks mapping
`tourism=*`		A place or object of specific interest to tourists.
`waterway=*`		Used to mark rivers or other kind of waterways.