Paul Corfield wrote:

The Billet roundabout is bloody horrible anyway - it was awful without
lights and not much better with them!


I would submit that the Great Cambridge Junction (where the A10, A111
and A406) has been made much, much worse.

Conveniently, "Bing" is still showing the old layout on their aerial
view, whilst Google show the new layout.

If you plonk "N18 1ND" into the searches on http://local.live.com/ and
Google Maps, then go to Aerial View, turn labels off and zoom in so the
scale is 100 yards on "bing" and 200ft / 50m on Google Maps you can see
the difference.

Starting from the right-hand side:

The left-hand lane of Silver Street (entering towards the middle of the
frame) is now a bus lane, with a banned left turn onto the A406
Eastbound at the traffic lights, forcing any traffic wanting to join the
A406(E) to proceed across the lights, and all the way round the
roundabout. (Not that that stops people from making an illegal left turn
anyway, usually in front of a bus).

Every sliproad onto the roundabout now has traffic lights, two sets in
the cases of the A10(N), A406(E) and A406(W) due to the additional roads
before the roundabout on these approaches, with further lights on the
roundabout itself before each on slip. These are phased in such a way
that too much traffic builds up in the "holding area" before the
roundabout, which results in long waits most of the time.

The A111 (Hedge Lane), which comes off of the A10 (Great Cambridge Road)
Northbound at an approximate 45 degree angle, has been converted from
two way traffic between the junction with the A10 and Taplow Road (the
road linking Hedge Lane and the A406 East) to one way, as has Taplow
Road itself, so traffic heading from the A111 onto the A10 (North) and
from the A406 (East) to the A111 (North West) or A10 (North) has to go
round the roundabout.

All of these changes have resulted in the junction becoming unusable for
much of the day, unless you want to go straight through the underpass on
the A406.

And don't even get me started on the chaos that ensues when the
underpass is closed, which results in TfL Streets denying that there's
no warning of the closure. (First warning sign being located *after* the
last possible point at which you can exit the A406 before the roundabout!)

Cheers,

Barry