"Traffic circles" - no, "Roundabouts" is a much more colourful name, and that's what they are called. Dead easy to negotiate once you'd got the knack.

Harlow probably has the largest concentration in the country. The legend is that when Sir Frederick Gibberd, the Harlow Master Planner had made the Master Plan for the New Town, he had a party, with the big map on the table. Only it was so big it took up all the table, and the guests put their drinks down on it, and left lots of little round marks all over the place. And that is why we have all these roundabouts.

They work pretty well. Originally the idea was there'd be no need for traffic lights, but now we've got a good number of them as well, and some roundabouts have traffic lights incorporated. If it all serves to confuse the tourists from benighted places where they don't have roundabouts, maybe that's a bonus...