It was, after all, a dramatic change. The old circle, 600 feet in diameter, that people were used to whizzing around at 30 to 40 mph was reduced to what seemed tiny - a roundabout measuring 200 feet across that slowed drivers' speeds considerably as a function of sheer geometry.

The interchange that joins some of the area's major thoroughfares - state Route 28, Washington Avenue, Col. Chandler Drive and the Thruway - was forever altered, a transition that state Department of Transportation officials say was difficult but ultimately worthwhile because of a dramatic reduction in the number of accidents there.

"The reduction in the accident rate is 65 percent. If you want to talk about personal-injury accidents, that's been reduced by greater than 85 percent," said Colleen McKenna, spokeswoman for the Department of Transportation.

McKenna said that during the three years prior to the redesign, an average of eight accidents per month were recorded by local law-enforcement agencies at the traffic circle. During the six months that followed the completion of the roundabout and the installation of signs - from February to August 2001 - there were only 2.8 accidents per month.

"We knew that once people got used to it, this is what would happen, and it did and it's great," McKenna said. "The average daily delay has also been reduced significantly. That, of course, is because it's a constant flow of traffic now."

McKenna said the success of the roundabout is helping the Department of Transportation promote this type of interchange as a replacement for large traffic circles and multiple-entrance intersections. A significant change from the old circle to the new roundabout is that drivers who merely need to move from one spoke to the next - Chandler Drive to the Thruway entrance, for example - can avoid the rotary altogether by using new access roads.

The Department of Transportation already has installed a similar roundabout on Long Island, has had public hearings and design sessions concerning proposals in Broome and Westchester counties and is in the early stages of considering a roundabout in the Raymond Avenue area of Poughkeepsie.

McKenna said the department learned some lessons from the local experience that will help it improve future projects. "I think that our public outreach was good, but it can always be better," she said. To that end, the Department of Transportation's Web site now includes a special section on modern roundabouts.

Local drivers who objected to the new roundabout at the outset now say they're more comfortable navigating the interchange, but they still question the need and $2.7 million expense.

"If it's a lower accident rate the state wanted to see there, they probably accomplished that, however, not by better design. More by a higher 'fear factor,'" said Albert Bruno of Kingston, who last year dubbed the roundabout "Malfunction Junction."

"While I have gotten used to it over the last year, I still feel the state could have accomplished the same end result, spending a lot less of taxpayers' money," Bruno said.

Bruno suggested the speed limit on Chandler Drive could have been reduced, stop signs at entrances to the roundabout could have been better enforced and perhaps a traffic light system on the old circle could have accomplished the same goal.

Traffic volume at the interchange has remained constant at roughly 36,000 vehicles per day.