The rotary

New Urban News Technical Page by Andres Duany, Michael Morrissey, and Patrick Pinnell

In understanding the components of urbanism at any point along the Transect, it is useful to differentiate between the organization of movement and the organization of spatial enclosure. Within the broad class of urban components based on more or less circular forms, the circle, the circus, and the rotary differ in their movement and spatial organization. The circus (see June 2001 issue) has a high degree of spatial definition, and usually also strongly organizes movement.  The rotary, by contrast, has as its goal the accomplishment of regular movement no matter what the character of the associated space.

The rotary is a device which uses a curving movement pattern to gather and stabilize disorderly and varied movement trajectories. It standardizes and reconciles potentially conflicting traffic volumes, speeds, and geometries. The rotary is  deliberately indifferent to difference, and that is precisely its usefulness.