2/5. The Roundabout. More British than the red phone box, the roundabout is the jewel in the crown of British traffic engineers. But, horror of horrors, it is a French invention that the British made their own. Joe Ken - visits
Letchworth, the site of the very first one opened in the UK in 1910 and hears of the difficulties the early motorists had in understanding how it worked. Producer Matthew Dodd