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
Magic Roundabout (Colchester) Magic Roundabout (Colchester) The Greenstead roundabout is a magic roundabout in Colchester, Essex. It is a large ring junction comprising five mini roundabouts, with two lanes in each direction joining each to its neighbour. It is known for its complexity, and the resulting confusion it causes for some motorists. The nickname "magic roundabout" comes from the television programme, "The Magic Roundabout", which was popular in the 1970s, when this novel layout was devised. It is located between the Hythe and Greenstead areas of the town, with the A133 (St Andrew's Avenue); Avon Way; Greenstead Road and the A134 (Elmstead Road).