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Public-images-osm logo.svg highway = turning_circle
Cul-de-Sac cropped.jpg
A widened area of road that allows vehicles to turn more easily. Show/edit corresponding data item.
Rendering in OSM Carto
Group: highways
Used on these elements
may be used on nodesshould not be used on waysshould not be used on areasshould not be used on relations (except multipolygon relations)
Useful combination
Status: approvedPage for proposal

A turning circle (known in American English as a "cul-de-sac" or "knuckle") is a widened area of road that allows vehicles to turn more easily. Often, but not always, a turning circle is circular in shape and located at the end of a  dead-end street ("cul-de-sac street", "blind alley", "close", "no through road"), resembling a frying pan. Either there is no central island or the island is traversable (for example, not taken up by parking spaces or greenery).

Where to find them

A turning circle may occur along a road instead of at the end. This can happen when more houses are built later and the road is extended. The nodes of 58489782 (achavi, OSMLab) on way Arthur Road, Wokingham are examples of this. Typically houses leading up to and on the turning circle are noticeably older than the houses beyond it.

In the United States, turning circles are very common in suburban planned residential areas. In some areas, every street ends in a turning circle (in which case it is called a "cul-de-sac"), and a turning circle may appear at every bend in a road (in which case it is called a "knuckle").

How to map

Place a node that is part of the road at the center of the widened area and add highway=turning_circle.

To specify the size of the turning circle, set diameter=* to the diameter, specifying the unit of measurement, for example diameter=10 m, diameter=12.5 m, diameter=70', etc. If the turning circle is rectangular and not circular, use the shorter of the two axes.

turning_circle=* is sometimes used to clarify the shape of the turning circle, in case it is not a classic circle. For example, turning_circle=hammer indicates a T-shaped turnaround area at the end of a street, and turning_circle=knuckle indicates a turning circle at an L-shaped bend in the road.

When not to use

For a more detailed comparison of these features, see Circular and widened road features



OSM Carto
Photo / Icon Highway types Remarks
For a range of highway types, eg
A turning circle is typically rendered as a circle at higher zooms, in the same style as residential or unclassified highways.
Turning circle on highway track-16.svg For highway=track


As with most tags in OpenStreetMap, this tag is based on the British English term "turning circle", and refers to turning places regardless of shape, including circular, square, triangular and otherwise.

See also