M4 EAST

A LONDON TO South Wales road was first proposed in the 1930s. Work began in the late 1950s/early 1960s. The Chiswick flyover in west London – built in 1959, not as a motorway – became Junction 1 of the M4 and is now considered the second oldest stretch of UK motorway. The Maidenhead bypass was the next part to open, in 1961. The remaining English section – 119 miles long, as far as the Severn Bridge – was built between 1961