A Primer On Roundabouts

The Region of Waterloo presents an animated tutorial and website about how to use a roundabout.

1 minute read

October 27, 2004, 5:00 AM PDT

By Chris Steins @planetizen


"Traffic circles have been part of the transportation system in the United States since 1905, when the Columbus Circle designed by William Phelps Eno opened in New York City. Subsequently, many large circles or rotaries were built in Canada and the United States. The prevailing designs enabled high–speed merging and weaving of vehicles. Priority was given to entering vehicles, facilitating high–speed entries. High crash experience and congestion in the circles led to rotaries falling out of favor in North America after the mid–1950’s. Internationally, the experience with traffic circles was equally negative, with many countries experiencing circles that locked up as traffic volumes increased.

...A modern roundabout typically results in less negative environmental impacts than a signalized intersection because it creates shorter delays to motorists and shorter vehicle queues. The longer delays associated with traffic signals result in more vehicles idling for longer periods."

Thanks to The Practice of New Urbanism

Tuesday, October 26, 2004 in Regeneration And Renewal

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I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching. Mary G., Urban Planner

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

Mary G., Urban Planner

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