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 a former public house, called The Plough, which faced the junction between Lawn Lane and Two Waters Road.
Despite its name, the Magic Roundabout is not actually a single roundabout.
It was constructed in 1973 to reduce the congestion at the original standard layout roundabout where seven roads intersected, it was one of the first bi-directional roundabouts to be constructed in the UK. At the junction of each road with the roundabout a mini-roundabout is present and subject to the normal clockwise direction of travel for all traffic. Between these mini-roundabouts however traffic is permitted to travel clockwise or anti-clockwise around the larger roundabout, the expectation being that drivers would choose the shorter route with less stationary traffic.
The Magic Roundabout in Hemel Hempstead was voted the UK's second-worst roundabout in a 2005 poll held by an insurance company (the winner being its Swindon counterpart).
In 2011 the roundabout was voted the best in Britain by motorists in a competition organised by a car leasing service.
Early history 
The original magic roundabout had six exits in total, with the British Petroleum building spanning "Marlowes", the road leading to the town centre, in the approximate position of the earlier railway Viaduct. The BP building was found to be unstable due to defective reinforced concrete and the exit had to be closed. This building was later demolished and the original route not restored, although a newer side exit from the roundabout replaced the junction with Marlowes off a side road.
Prior to this design, a number of schemes were tried, including widening some of the entrances to and exits from the roundabout: ultimately a spiral roundabout was trialled. The idea behind this scheme was that drivers were supposed to enter the clockwise only roundabout, go to the center and then, about two exits before their chosen exits get into a lane that would spiral them off. The spiral idea failed, as many drivers ignored the lane markings, while those who followed the spiral tended to accelerate as they went round.
The present scheme opened in June 1973 and caused tailbacks allegedly to Berkhamsted, and up St Alban's Road, almost as far as the M1 in the other direction. A police officer had to be stationed at each of the mini roundabouts to prevent chaos.
When the new junction was first opened, a camera was placed overlooking the roundabout on the roof of the adjacent Kodak HQ building. It was noted many drivers would get 'lost' and make repeated reversals of direction between joining the roundabout and eventually leaving it.
Other similar roundabouts 
- Magic Roundabout (Swindon), a Magic Roundabout in Swindon.
- Magic Roundabout (Colchester), a Magic Roundabout in Colchester.
- Denham Roundabout, Denham, Buckinghamshire at Junction 1 of the M40 and the meeting of the A40, A412 and A4020 roads.
- Hatton Cross, at the southeast corner of Heathrow Airport, just outside Hatton Cross Underground station. This is especially challenging due to the large number of delivery drivers under pressure to meet airport dealines mixing with drivers dropping off passengers who are unfamiliar with the roads around Heathrow.
- Sadler's Farm Roundabout, a Magic Roundabout near Southend-on-Sea, Essex.
- Brits vote on the best and worst roundabouts, 20 December 2005, retrieved on 2008-01-18
- We’re the top roundabout? That’s Magic! , Hemel Gazette, 20 May 2011,
|Wikimedia Commons has media related to: Magic Roundabout (Hempstead)|
- History of the roundabout at the Hemeltoday website
- BBC discussion forum on the Plough roundabout
- Google Maps satellite image view