A40(M) High Wycombe Bypass
Where was it?
High Wycombe, Buckinghamshire (plus it goes across the Oxfordshire border!)
Not London, then?
No...
Ah, I see.
Well, instead of being nowadays part of the A40, it's actually part of the M40!
Can you show me where it was on a map?
When was it built?
In 1969
And when did it become part of the M40?
Not long after it opened - in 1970 by the latest!
Why did it change its number?
Given that I have a map showing the same stretch of road labelled as M40, it's probably down the someone at the Ministry of Transport having a "hang on a minute, that's not really just a bypass built to motorway standards" moment.
I'd love to hear from anyone who knows the real reason!
You can see the full version of the map shown above here.
Can I comment on this motorway?
Of course! Contact me and I'll put them here!
Have any other visitors commented?
Peter Harris starts off, with some interesting information about the early days of the M40...
"I have just consulted my Father who agrees with me that the M40 has always been called the M40. (We have lived in the Wycombe area since 1965).
The first section to be built was from Handycross (A404) present junction4 to Stokenchurch (Junction 5) which opened in 1967. The next section was from Handycross to a temporary terminal at Wycombe End, Holtspur. This bit opened in 1969. I have a 1969 RAC atlas which shows these two sections opened as M40 with junction nos 3-5.
Your map shows the present day site of junction 3 at Loudwater as being open together with the temporary terminal at Holtspur (also Junction 3), so I would cast doubt on anything else it represented. As a matter of fact, the temporary terminal was abolished when the Beaconsfield bypass opened to (the re-routed A355) Junction 2, in 1971, The new junction 3 opened in 1972.
It was watching the various bits of the M40 being built and then going for a ceremonial first ride on them, which fired my interest in roads and motorways, so I remember the chain of events very well.
Nick Stevenson remembers a mapping problem...
I think that on one page of the AA Members' Handbook of the period (when the High Wycombe by-pass was being extended towards Beaconsfield?) the confusion over the correct nomenclature led to the new(er) bit being shown as "M40(M)" ! (Shades of the A74...).