Where is it?
On the Bedfordshire section of A1, notorious as an ancient section of A1 full of roundabouts and right-turns, where the A421 trunk route from Bedford joins in.
What's wrong with it?
This whole section of A1 is at best unacceptable, and at worst downright dangerous. The Black Cat Roundabout is certainly a contender for the most dangerous junction on it. Considering this stretch of all-purpose A1 is between two sections of A1(M), the place where it meets another trunk route (and one which is a grade separated dual carriageway just a few miles further on) is not the place for a cramped roundabout. The Black Cat is a regular on traffic reports for overturned lorries and general congestion as the sheer volume of traffic finds it hard to get through.
Why is it wrong?
This section of the A1 was upgraded quite a while before the sections around it — it was dualled when the rest of the road was still single carriageway, by slapping another two lane carriageway next to the existing one. Back in the 1950s it must have been a dream, but now, stuck between two sections of fast A1(M), it's abysmal and traffic using it isn't used to travel on such a low-grade overused road. This junction simply hasn't been updated and is long overdue for an overhaul.
What would be better?
The A421 upgrade works could have included a new junction. It wouldn't be achieving the impossible to build a new roundabout with the A1 flying over the top — basic and very much a plain-vanilla option but it would be perfectly adequate here. Sadly all that happened was that the existing roundabout was made larger. Alternatively, since there's no other roads involved, how about a free-flowing trumpet, costing not much more in land, less in overbridges, and returning more in capacity?
Right to reply
I thought it WAS being replaced with a grade seperated junction and a connection from the A421 to the A428?