Part the road has been diverted to make way for Heathrow Airport, while another stretch was originally planned to be Ringway 3, one of four major ring motorways around London.

[2] Later, a new road called The Causeway was built, cutting between the two balancing reservoirs of Heathrow's water pollution control.

[3] In November 1975, the Transport Minister John Gilbert announced that the sections of Ringway 3 in south and west London, including the Parkway, were cancelled.

[4] The Hayes Bypass section of The Parkway was opened, after long delay, in September 1992,[5] cutting through Bulls Bridge, Pump Lane Industrial Estate and Yeading.

[8] The new trunk road provided relief to Hayes town centre and eventually led to it to be pedestrianised.