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 (Staffordshire) and the Hatton Cross Roundabout in London. Churchbridge Junction in Staffordshire is a magic gyratory. This type of junction is similar to a magic roundabout, except that the constituent roundabouts are connected by longer lengths of roadway. Tram roundabouts, which are found in many countries, merge roundabouts for individual vehicles with tram lines. Large areas are needed for tram roundabouts that include a junction between tram lines. Such systems often contain tram stops. Tram rails usually cross roundabouts in the center. This requires traffic lights or special signalling granting the trams priority. However, there are also roundabouts where trams