"Martin Underwood" wrote in message
s.com...
... Interesting that the junction was
constructed with single-lane slip roads leading from a (presumably) 3-lane
M1 to a (presumably) 2-lane A1, rather than making the slip roads 2-lane
as
you'd get at any motorway junction nowdays.

South of the M10, the M1 used to be two-lane. In those days, most of the
traffic used the M10 for access and it was possible (although unusual enough
for me to remember it happening) to drive from London to Luton without
seeing another vehicle travelling in the same direction.

Colin Bignell