Where I live is now by-passed - it is unthinkable how it would be without it.
I can remember the long queues in the 1950s to get through Doncaster.
I can also remember the first time that we drove along the Doncaster bypass at undiminished speed.
What isn't mentioned is that Ernest Marples (who served as Minister of Transport) was a director of Marples Ridgway (a civil engineering contracting company).
Marples also initiated the Beeching report that saw the closure of much of the railways.
http://en.wikipedia.org/wiki/Ernest_Marples