Roundabout constructed in 1972 in Swindon, Wiltshire, United Kingdom, designed by Frank Blackmore, inventor of the mini-roundabout. The roundabout joins five roads and consists of a two-way road around the central island, with five mini-roundabouts meeting the incoming roads. The name derives from the popular children's television series, "The Magic Roundabout", and is considered "magic" because traffic flows in both clockwise and anticlockwise directions. This is achieved by surrounding the main island with one smaller roundabout per entry/exit street. This pattern directs traffic in the usual clockwise (in LHT installations) or counter-clockwise (in RHD installations) manner around each mini-roundabout. Exiting the
Denham Roundabout round it clockwise in the usual way, but as traffic volumes built up, the layout was altered so that the traffic moved round the roundabout in both directions, making it a ring junction with mini-roundabouts at the points that other roads join the main roundabout. Denham Roundabout The Denham Roundabout is where Western Avenue, the A40, flows into the M40 motorway. The roundabout below facilitates junction 1 (J1) of the motorway to connect with the westbound continuation of the A40, together with the intersection of the road from Uxbridge (A4020) and the road from Slough to Watford (A412). When the