MultiPlex A421 Bedford Bypass

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JohnnyMo
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MultiPlex A421 Bedford Bypass

Post by JohnnyMo »

I have noticed some interesting quirks about the Bedford Bypass.

The A421 starts at the Black Cat roundabout, this creates a unnecessary multiplex with the A428.
One Section of the bypass is a triple-plex A421 (A6)(A428)
This section must be one of a few multiplexes where a higher numbered road take precedence (makes sense, but unusual).
The A428 is multiplexed by the A1, A421 and A6 before continuing.

Are there any other triple-plexes or more?
Any other road has three or more successive multiplexes before continuing.
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Re: MultiPlex A421 Bedford Bypass

Post by SouthWest Philip »

Wallingford has the A4074, A4130, A329 and B4009 in the same multiplex. Don't think there are any with more than four.
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Re: MultiPlex A421 Bedford Bypass

Post by B1040 »

Kettering bypass is a mix of A14, A6 and A 43, numbered A14 as that's the most important one.
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Re: MultiPlex A421 Bedford Bypass

Post by ForestChav »

From M1 J15 the road is A45 but the section north of that also multiplexes with A43 and A508. The A43 and A45 also multiplex with the M1 from J15a and 16.
C, E flat and G go into a bar. The barman says "sorry, we don't serve minors". So E flat walks off, leaving C and G to share an open fifth between them.

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Re: MultiPlex A421 Bedford Bypass

Post by JohnnyMo »

SouthWest Philip wrote: Thu Jun 30, 2022 15:43 Wallingford has the A4074, A4130, A329 and B4009 in the same multiplex. Don't think there are any with more than four.
Also the A4074 takes precedence over A329
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Re: MultiPlex A421 Bedford Bypass

Post by ForestChav »

JohnnyMo wrote: Thu Jun 30, 2022 16:16
SouthWest Philip wrote: Thu Jun 30, 2022 15:43 Wallingford has the A4074, A4130, A329 and B4009 in the same multiplex. Don't think there are any with more than four.
Also the A4074 takes precedence over A329
I know this is more of a staggered crossroads than a multiplex, but still, the A40 double TOTSOs with a B road, which keeps the mainline.

Anyone remember what this was like before the M40? I wasn't born
C, E flat and G go into a bar. The barman says "sorry, we don't serve minors". So E flat walks off, leaving C and G to share an open fifth between them.

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Re: MultiPlex A421 Bedford Bypass

Post by ForestChav »

Anyway, I'm sure there are plenty of examples of double/triple/whatever multiplexes on inner ring roads or if the roads in a town or village converge on a central point such as a high street or a bridge before diverging again.

I think pretty much all of the Direby inner ring is the A601, but the A6 and A52 both enter and leave it twice.

Likewise the A5460, A6, A47 with the A594 in Leicester (would previously have also had the A50 in there before it was renumbered).
C, E flat and G go into a bar. The barman says "sorry, we don't serve minors". So E flat walks off, leaving C and G to share an open fifth between them.

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Re: MultiPlex A421 Bedford Bypass

Post by Mapper89062 »

A part of the Chelmsford bypass is a multiplex of the A12, A414 and A130 (although my understanding is that the A130 stub north of Chelmsford will become A131 when it is rerouted onto the new NE bypass, so this will not exist for much longer.)

There must be quite a lot on city centre inner ring roads, like Cambridge (A603/A1309/A1307), Derby (A601/A6/A52) and Wolverhampton (A4150/A449/A41/A454) although many depend on which direction round the city you consider the road to multiplex.
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Re: MultiPlex A421 Bedford Bypass

Post by JohnnyMo »

ForestChav wrote: Thu Jun 30, 2022 16:24
JohnnyMo wrote: Thu Jun 30, 2022 16:16
SouthWest Philip wrote: Thu Jun 30, 2022 15:43 Wallingford has the A4074, A4130, A329 and B4009 in the same multiplex. Don't think there are any with more than four.
Also the A4074 takes precedence over A329
I know this is more of a staggered crossroads than a multiplex, but still, the A40 double TOTSOs with a B road, which keeps the mainline.

Anyone remember what this was like before the M40? I wasn't born
Looking at Sabre Maps (1" to 1 mile OS) the B4009 ran along Butts Way to the A40 ( Staggered Junction) and continues along the High St straight into Lewknor
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Re: MultiPlex A421 Bedford Bypass

Post by owen b »

JohnnyMo wrote: Thu Jun 30, 2022 15:21 This section must be one of a few multiplexes where a higher numbered road take precedence (makes sense, but unusual).
I don't think it's particularly unusual. I've had a quick look at the route of the A6 and I reckon it's the subordinate multiplex on at least eight occasions (Bedford twice, Kettering, Leicester, south of Derby, Derby, Manchester, south of Kendal).
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Re: MultiPlex A421 Bedford Bypass

Post by ForestChav »

owen b wrote: Thu Jun 30, 2022 19:02
JohnnyMo wrote: Thu Jun 30, 2022 15:21 This section must be one of a few multiplexes where a higher numbered road take precedence (makes sense, but unusual).
I don't think it's particularly unusual. I've had a quick look at the route of the A6 and I reckon it's the subordinate multiplex on at least eight occasions (Bedford twice, Kettering, Leicester, south of Derby, Derby, Manchester, south of Kendal).
The A6 isn't really a major road in any of those areas though. Towards the south it's superseded by the M1 up until south of Derby then it's a scenic route through the Peak District. North of Manchester it's paralleled almost completely by the M61 and M6. The only time it's not being doubled up by a motorway is between Derby and Stockport.
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Re: MultiPlex A421 Bedford Bypass

Post by roadphotos »

Has anyone noticed that almost every junction on the A421 between the A1 and M1 has incorrect signage. The mileage sign after the A421/A1 junction at Black Cat says 'Bedford A428' (should be A4280) then all of the signage at the next exit (before and at the junction) still says A428 as the road number at the exit even though the road number is actually the A4280 and has been for over 10 years. The first sign on the westbound off slip at the A421/A6/A5141 junction still shows the A6 towards Bedford when it's actually the A5141, the second sign on the same slip road shows it correct as the A5141 so the signage is inconsistent. The signs for the Marsh Leys Junction show the road at the junction as the A428 when it's actually the A6 and finally the signs on the A421 on the approach to (and at) the A507/M1 (south) junction still say 'Woburn A4012' even though the road number was changed to the B5704 in 2017.
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Re: MultiPlex A421 Bedford Bypass

Post by Bryn666 »

ForestChav wrote: Thu Jun 30, 2022 16:24
JohnnyMo wrote: Thu Jun 30, 2022 16:16
SouthWest Philip wrote: Thu Jun 30, 2022 15:43 Wallingford has the A4074, A4130, A329 and B4009 in the same multiplex. Don't think there are any with more than four.
Also the A4074 takes precedence over A329
I know this is more of a staggered crossroads than a multiplex, but still, the A40 double TOTSOs with a B road, which keeps the mainline.

Anyone remember what this was like before the M40? I wasn't born
The A40 took priority originally. The stagger was built with the M40. SABRE Maps has t'answer.
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Re: MultiPlex A421 Bedford Bypass

Post by trickstat »

roadphotos wrote: Thu Jul 07, 2022 17:46 Has anyone noticed that almost every junction on the A421 between the A1 and M1 has incorrect signage. The mileage sign after the A421/A1 junction at Black Cat says 'Bedford A428' (should be A4280) then all of the signage at the next exit (before and at the junction) still says A428 as the road number at the exit even though the road number is actually the A4280 and has been for over 10 years.
That sounds like it just hasn't been updated or replaced at all since the new road has been built. Also I would assume that Bedford would be signposted along the A421 via (I would think) the A603 rather than the A4280.
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Re: MultiPlex A421 Bedford Bypass

Post by KeithW »

trickstat wrote: Sat Jul 09, 2022 09:25 That sounds like it just hasn't been updated or replaced at all since the new road has been built. Also I would assume that Bedford would be signposted along the A421 via (I would think) the A603 rather than the A4280.
Well approaching the turn off to the A4280 from the Black Cat the sign actually reads
Bedford (A428) and sure enough if you follow the A4280 through Bedford you end up on the A428. Its also the most direct route to Bedford.

Follow the A421 from the Black Cat past that turn and you will have to to take the A6 to get onto the A428.

As for the A630 its not a viable route from anywhere north of Sandy and while Moggerhanger is a nice place I would hesitate to send much traffic that way. The Cambridge to A1 road was of course the A45 until the 1990's.

In the long term the best solution in my opinion is to renumber the A428 from Cambridge to the A1 as A421. The A421 would then run all the way from Cambridge through Milton Keynes and Buckingham to the A43 and the A4280 can have its original number back.
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Re: MultiPlex A421 Bedford Bypass

Post by roadphotos »

That's exactly what's going to happen when the Black Cat to Caxton Gibbet dualling is complete in a few years time. The road between the M11 and A14 at Cambridge and the A1 (south of St Neots) is going to renumbered as part of the A421.
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Re: MultiPlex A421 Bedford Bypass

Post by trickstat »

KeithW wrote: Sat Jul 09, 2022 13:38
trickstat wrote: Sat Jul 09, 2022 09:25 That sounds like it just hasn't been updated or replaced at all since the new road has been built. Also I would assume that Bedford would be signposted along the A421 via (I would think) the A603 rather than the A4280.
Well approaching the turn off to the A4280 from the Black Cat the sign actually reads
Bedford (A428) and sure enough if you follow the A4280 through Bedford you end up on the A428. Its also the most direct route to Bedford.

Follow the A421 from the Black Cat past that turn and you will have to to take the A6 to get onto the A428.

As for the A630 its not a viable route from anywhere north of Sandy and while Moggerhanger is a nice place I would hesitate to send much traffic that way. The Cambridge to A1 road was of course the A45 until the 1990's.

In the long term the best solution in my opinion is to renumber the A428 from Cambridge to the A1 as A421. The A421 would then run all the way from Cambridge through Milton Keynes and Buckingham to the A43 and the A4280 can have its original number back.
While I know that the A4280 would be the shortest route from the Black Cat to Bedford, I wasn't sure whether it would be the signposted route to the town as you possibly have to travel through more of the town to reach the centre that way than you would if you stayed on the A421 and exited at the A603 (I wasn't suggesting going through Moggerhanger btw). However, the A4280 does have the advantage of keeping you north of the Ouse.
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Re: MultiPlex A421 Bedford Bypass

Post by ForestChav »

Bryn666 wrote: Sat Jul 09, 2022 00:38
ForestChav wrote: Thu Jun 30, 2022 16:24
JohnnyMo wrote: Thu Jun 30, 2022 16:16

Also the A4074 takes precedence over A329
I know this is more of a staggered crossroads than a multiplex, but still, the A40 double TOTSOs with a B road, which keeps the mainline.

Anyone remember what this was like before the M40? I wasn't born
The A40 took priority originally. The stagger was built with the M40. SABRE Maps has t'answer.
Well that's what I'd wondered, given that pre-M40 the A40 would have been without doubt the main route but then relegated to local traffic, and if it had been a TOTSO with the B road then it would have surely been a bottleneck.

On the A421/A428 mess, which is what it is... It's clearly far more logical to have the M1-A1 link with the same number. But you have a fair amount of work to do, to find the A428 if you follow it out of Cambridge to the A1, and then wonder where else it goes. Of course, it actually resurfaces the other side of Bedford and heads on to Coventry. The A4280 situation is a bit silly, in all honesty, if the intention is to take traffic out of Bedford, then it perhaps needs to be a B road, as it stands to get from the bypass to the A428 the A6 is more logical. As would be the intention to ultimately end the A428 on the A6 at that point, even though it wouldn't have any obvious benefits of renumbering the East section of ex-A45 to something else, other than tidiness.

Extending the A421 like that has really caused a bit of a numbering hassle...
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Re: MultiPlex A421 Bedford Bypass

Post by ForestChav »

Been looking at this in more detail and I'd never noticed how drastically the A421 has changed over the years. Seems only a very small section of it was the initial route and to the East it's had significant changes.

Though extending it from Buckingham to Milton Keynes made more sense as soon as the latter existed (with the M1 being a much more logical end for it than the A5) I wonder why they chose to then extend the number to the A1 rather than taking a completely new number or re-routing an existing road.

It looked much more logical on the older maps with the A45 heading through St Neots (and sending out a spur to the A1) with the A428 ending on the A1 at the Black Cat, so both extending the A428 past the A1 and extending the A421 to the A1 makes both look untidy now.

I get that the traffic importance of linking Cambridge with the A1 meant that they probably needed to keep that section an A-road and primary, and that the section of A45 west of the A1 needed to be a B road especially to keep people out of places like Kimbolton, but, it's that which has caused the numbering mess of extending the A421, as it was a bit of a weird multiplex anyway, and means the A428 can't just end sensibly on the A6 where it does at the moment (though my OS map shows the section of road to the East of that as A4280, which I'm assuming is a mistake, because it'd be a bit of a useless multiplex with the A6 otherwise). Wonder why they chose the A428 for that section and not another number, when they rightly decided it couldn't really be the A45 once they'd renumbered the other sections?
C, E flat and G go into a bar. The barman says "sorry, we don't serve minors". So E flat walks off, leaving C and G to share an open fifth between them.

Never argue with an idiot. They will bring you down to their level and beat you with experience.
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Re: MultiPlex A421 Bedford Bypass

Post by KeithW »

trickstat wrote: Sat Jul 09, 2022 16:27 While I know that the A4280 would be the shortest route from the Black Cat to Bedford, I wasn't sure whether it would be the signposted route to the town as you possibly have to travel through more of the town to reach the centre that way than you would if you stayed on the A421 and exited at the A603 (I wasn't suggesting going through Moggerhanger btw). However, the A4280 does have the advantage of keeping you north of the Ouse.

At the end of the day the best route depends on where in Bedford you are heading for and where you are starting from and the traffic on the day.

From Sandy to Bedford centre the shortest route is the A603, its the way I would go.

From St Neots to Bedford the alternatives are shown below timings and distance from Google maps
A1/A421/A4280 - 10.7 miles/20 minutes
A1/A421/A603 - 11.9 miles/21 minutes

If the Black Cat is throwing a Mare then I have been known to take the back roads to Colmworth and the B660
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