Magic Roundabout (Hemel Hempstead) viaduct. The BP building was found to be unstable due to defective reinforced concrete and the exit had to be closed. The building was demolished but the original route was not restored, although a newer side exit from the roundabout replaced the junction with Marlowes off a side road. Magic Roundabout (Hemel Hempstead) The "Magic Roundabout" in Hemel Hempstead, Hertfordshire, England, is the familiar name given to the Plough roundabout. The familiar name comes from the children's television programme, and is also used for a similar junction in Swindon and the M40 junction in Denham. The official name relates to
Roundabout first modern roundabout in the United States was constructed in Summerlin, Nevada in 1990. This roundabout occasioned dismay from residents, and a local news program said about it, "Even police agree, [roundabouts] can be confusing at times." As of the beginning of the twenty-first century, roundabouts were in widespread use in Europe. For instance, in 2010 France had more than 30,000 roundabouts. A "modern roundabout" is a type of looping junction in which road traffic travels in one direction around a central island and priority is given to the circulating flow. Signs usually direct traffic entering the circle to slow