"Terry Harper" wrote in message
...
"Martin Underwood" wrote in message
...
"Terry Harper" wrote in message
...

It seems to work well from Junction 10 (A3) onwards clockwise on the
M25.
In
general 4 lanes between junctions, three lanes through them.

And do "tortoise" vehicles have to keep changing lanes as they approach
and
leave each junction?

Have you never driven round the M25? Nobody "has" to do anything. The
overhead signs in advance of each junction clearly indicate that the
nearside lane is exit only from that point onwards. Depending on how far
it
is between junctions, then vehicles may move to the nearside lane or stay
in
the second lane. Between Junction 11 (Chertsey) and Junction 12 (M3) only
vehicles wanting to leave on the M3 are usually to be found in the
nearside
lane, because it is a short distance. The advantage is that it gives
vehicles a much better chance of getting into the exit lane well in
advance
of the junction, and stops much of the last-minute darting for the exit
that
you find elsewhere.

But this isn't why it is like that.

It is because when they widened to 4 lanes it was too expensive
to rebuild the junction so the extra lane was only built between
the junctions. As you say it works well, but I don't think that they
often do it that way by design.

tim


--
Terry Harper, Web Co-ordinator, The Omnibus Society
Web Site: http://www.omnibussoc.org/75th.htm
E-mail:
URL: http://www.terry.harper.btinternet.co.uk/