Columbus Circle, New York City, NY; site of the first traffic circle in the United States completed in 1905

DeSoto Fountain sits in the center of a traffic circle in the city of Coral Gables, Florida.
Photo: Marc Averette

This traffic circle in front of the county courthouse in Angola, Indiana, would be considered a roundabout in the UK. It merely requires entering traffic in all four directions to yield. The island is blocked to traffic or parking by a war memorial. Parking is allowed on the outskirts in place of a weaving area.

Signage for a traffic circle in New Jersey

A traffic circle is an intersection with a circular shape and, usually, a central island. In some traffic circles two-way traffic is allowed within the circle. It is much more common, however, that traffic is allowed to go in one direction only around a central island. In some traffic circles, entering roads are controlled by stop signs or traffic signals. In other cases, traffic enters the circulatory roadway by merging, sometimes at relatively high speeds. Traditionally, traffic entering a circle has the right-of-way, although some circles give right-of-way to the primary roads. In roundabouts, as opposed to traffic circles, entering traffic must yield to traffic already in the circulatory roadway. Image File history File linksMetadata Download high-resolution version (2400x1600, 607 KB) Photo of Columbus Circle, New York City, from the third floor balcony in the foyer of the Time Warner Center, looking east down 59th Street. ... Image File history File linksMetadata Download high-resolution version (2400x1600, 607 KB) Photo of Columbus Circle, New York City, from the third floor balcony in the foyer of the Time Warner Center, looking east down 59th Street. ... Columbus Circle Columbus Circle is a major landmark and point of attraction in New York City. ... Image File history File links Size of this preview: 800 × 600 pixel Image in higher resolution (1280 × 960 pixel, file size: 249 KB, MIME type: image/jpeg)Digital Photo taken by Marc Averette I, the creator of this work, hereby release it into the public domain. ... Image File history File links Size of this preview: 800 × 600 pixel Image in higher resolution (1280 × 960 pixel, file size: 249 KB, MIME type: image/jpeg)Digital Photo taken by Marc Averette I, the creator of this work, hereby release it into the public domain. ... DeSoto Fountain sits in the center of a traffic circle in the city of Coral Gables, Florida. ... The City Beautiful Location of Coral Gables in Miami-Dade County, Florida. ... Image File history File links Size of this preview: 800 × 350 pixel Image in higher resolution (3000 × 1313 pixel, file size: 912 KB, MIME type: image/jpeg) Angola, Indiana downtown circle. ... Image File history File links Size of this preview: 800 × 350 pixel Image in higher resolution (3000 × 1313 pixel, file size: 912 KB, MIME type: image/jpeg) Angola, Indiana downtown circle. ... Official language(s) English Capital Indianapolis Largest city Indianapolis Area  Ranked 38th  - Total 36,418 sq mi (94,321 km²)  - Width 140 miles (225 km)  - Length 270 miles (435 km)  - % water 1. ... For the song by Yes, see Roundabout (song) A roundabout or rotary is a type of road junction (or traffic calming device) at which traffic enters a stream around a central island after first yielding (giving way) to the circulating traffic. ... Image File history File linksMetadata Download high-resolution version (860x645, 140 KB) Route 34 at the Allaire Circle I, the creator of this work, hereby release it into the public domain. ... Image File history File linksMetadata Download high-resolution version (860x645, 140 KB) Route 34 at the Allaire Circle I, the creator of this work, hereby release it into the public domain. ... It has been suggested that this article be split into multiple articles. ... In the field of road transport, a road junction is a place where two or more roads either meet or cross. ... Nighttime traffic captured by a camera over several seconds. ... For the song by Yes, see Roundabout (song) A roundabout or rotary is a type of road junction (or traffic calming device) at which traffic enters a stream around a central island after first yielding (giving way) to the circulating traffic. ...

History

French architect Eugène Hénard was designing one-way circular intersections as early as 1877^[1]. American architect William Phelps Eno favored small traffic circles. He designed New York City's famous Columbus Circle, which was built in 1905. Other traffic circles were subsequently built in the United States. Many were large diameter 'rotaries' that enabled high speed merge and weave, and gave priority to the traffic entering the circle. These designs were doomed to failure for two primary reasons: 1877 (MDCCCLXXVII) was a common year starting on Monday (see link for calendar). ... William Phelps Eno (1858-1945) was an American businessman responsible for many of the earliest innovations in road safety and traffic control. ... Columbus Circle Columbus Circle is a major landmark and point of attraction in New York City. ... 1905 (MCMV) was a common year starting on Sunday (link will display the full calendar). ...

• It takes a large diameter circle to provide enough room for merging at speed. Despite the fact that some of these circles were huge (many were in excess of 100 meters or 328 feet in diameter), they weren't large enough for high-speed merging.
• Giving priority to entering traffic means that more vehicles can enter the circulatory roadway than it can handle. The result is congestion within the circle.

The experience with traffic circles in the US was almost entirely negative, characterized by high accident rates and congestion problems. By the mid 1950s, construction of traffic circles had ceased entirely. The experience with traffic circles in other countries was not much better until the development of the modern roundabout in the United Kingdom during the 1960s.

Among the most famous traffic circles in the world is that of Canberra, Australia, where a large traffic circle encircles Parliament House. This circle has traffic lights at each major intersection within the circle. For other uses, see Canberra (disambiguation). ... Parliament House Canberra: The main entrance and the flag Parliament House is the name given to a purpose-built building opened in 1988 in Canberra, the capital of Australia. ...

Composition

Traffic circles are often composed of concrete or asphalt although more recently rubber curbing is being used to create traffic circles as well, primarily in residential areas. Rubber curbing consists of units of flexible rubber that are bent and installed around a landscaped area to create traffic circles.

Source

1. ^ P. M. Wolf, Eugene Henard and the Beginning of Urbanism in Paris, 1900–1914, International Federation for Housing and Planning, The Hague, 1969, cited by Ben Hamilton-Baillie & Phil Jones, Improving traffic behaviour and safety through urban design, Proceedings of ICE - Civil Engineering, volume 158 Issue 5 May 2005 p. 41 http://www.hamilton-baillie.co.uk/papers/ICE_paper_April05.pdf

See also

• List of traffic circles in New Jersey
• List of Circles in Washington, D.C.
• Roundabout