Why are some Motorways numbered similar to A roads the replaced and others not?

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ajuk
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Why are some Motorways numbered similar to A roads the replaced and others not?

Post by ajuk »

Compare the M62, M45, M2, M27, M3, M4 and M6, are all numbered the same as A roads the bypass or in the case of M6 go mostly in the same direction, more recently the M48 is the perfect number for that road. The M1 is forgivable because it goes north and it was the first motorway. So what is going on with the M5? It's out of zone and an obvious number would be the M38 or the M50 rather than the M449 and as for the A601(M) why number a short spur as part of the Derby inner ring road, what were they sniffing?
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Re: Why are some Motorways numbered similar to A roads the replaced and others not?

Post by Chris5156 »

The short answer is because, in England and Wales, numbers are chosen based on the zone the motorway is in, not which A-road it follows. It's sometimes possible to allocate a number that also mirrors a nearby A-road and in a lot of cases that was done, but it's not a requirement.

Motorway zones are not the same as A-road zones. More here

In Scotland, of course, the rules are different, and motorways do take their number from the most appropriate parallel A-road.
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Re: Why are some Motorways numbered similar to A roads the replaced and others not?

Post by c2R »

ajuk wrote: Wed Oct 13, 2021 00:55 Compare the M62, M45, M2, M27, M3, M4 and M6, are all numbered the same as A roads the bypass or in the case of M6 go mostly in the same direction, more recently the M48 is the perfect number for that road. The M1 is forgivable because it goes north and it was the first motorway. So what is going on with the M5? It's out of zone and an obvious number would be the M38 or the M50 rather than the M449 and as for the A601(M) why number a short spur as part of the Derby inner ring road, what were they sniffing?
Note that the M6 was the first motorway, not the M1.
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Re: Why are some Motorways numbered similar to A roads the replaced and others not?

Post by Steven »

c2R wrote: Wed Oct 13, 2021 06:26
ajuk wrote: Wed Oct 13, 2021 00:55 Compare the M62, M45, M2, M27, M3, M4 and M6, are all numbered the same as A roads the bypass or in the case of M6 go mostly in the same direction, more recently the M48 is the perfect number for that road. The M1 is forgivable because it goes north and it was the first motorway. So what is going on with the M5? It's out of zone and an obvious number would be the M38 or the M50 rather than the M449 and as for the A601(M) why number a short spur as part of the Derby inner ring road, what were they sniffing?
Note that the M6 was the first motorway, not the M1.
Indeed, it was equal third with the M10 and M45. The M4 Chiswick Flyover opened second (though was signed as A4 at the time)

As Chris says, motorway numbering is completely separate from the all-purpose system. As well as the overview on roads.org.uk, there's an in-depth history told through the words of the very people involved can be found on PM.
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Re: Why are some Motorways numbered similar to A roads the replaced and others not?

Post by B1040 »

The M6 also provides relief to the A5, A34 and A49 as well as the A6 North of Preston.
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Re: Why are some Motorways numbered similar to A roads the replaced and others not?

Post by LoopyUpholland »

I would argue that it would be silly for a Motorway as long as the M5 to be M38 instead. I'd probably have also given the M62 a Mx number, given its importance, and that's to say nothing of the M25.
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Re: Why are some Motorways numbered similar to A roads the replaced and others not?

Post by KeithW »

LoopyUpholland wrote: Wed Oct 13, 2021 12:26 I would argue that it would be silly for a Motorway as long as the M5 to be M38 instead. I'd probably have also given the M62 a Mx number, given its importance, and that's to say nothing of the M25.
If by Mx you mean having a single digit that would be a problem. M7, M8 and M9 were reserved for Scotland while M1, M2, M4, M5 and M6 were already used before the M62 was built while M3 was already allocated to the London-Southampton motorway. The M25 as built was of course cobbled together from the planned routes of Ringway 3 north of London aka the M16 and Ringway 4, the South Orbital road referred to at the time as the M25.
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Re: Why are some Motorways numbered similar to A roads the replaced and others not?

Post by Bryn666 »

KeithW wrote: Wed Oct 13, 2021 14:00
LoopyUpholland wrote: Wed Oct 13, 2021 12:26 I would argue that it would be silly for a Motorway as long as the M5 to be M38 instead. I'd probably have also given the M62 a Mx number, given its importance, and that's to say nothing of the M25.
If by Mx you mean having a single digit that would be a problem. M7, M8 and M9 were reserved for Scotland while M1, M2, M4, M5 and M6 were already used before the M62 was built while M3 was already allocated to the London-Southampton motorway. The M25 as built was of course cobbled together from the planned routes of Ringway 3 north of London aka the M16 and Ringway 4, the South Orbital road referred to at the time as the M25.
And let's not forget that the M62 was the product of three separate motorway schemes being shoehorned into one.

*Liverpool-Eccles (M52)
*Stretford-Leeds (M62)
*Leeds-Hull(ish) (M19)

I can only presume that the M52 vanished quickly, as in 1969's "Motorways" by James Drake construction drawings refer to the M62, M63, and M64 (which was the original M602 number). This change of motorway plans is also why the M62 has a TOTSO at J12 and all the problems that has caused since.
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Re: Why are some Motorways numbered similar to A roads the replaced and others not?

Post by Bryn666 »

Steven wrote: Wed Oct 13, 2021 07:29
c2R wrote: Wed Oct 13, 2021 06:26
ajuk wrote: Wed Oct 13, 2021 00:55 Compare the M62, M45, M2, M27, M3, M4 and M6, are all numbered the same as A roads the bypass or in the case of M6 go mostly in the same direction, more recently the M48 is the perfect number for that road. The M1 is forgivable because it goes north and it was the first motorway. So what is going on with the M5? It's out of zone and an obvious number would be the M38 or the M50 rather than the M449 and as for the A601(M) why number a short spur as part of the Derby inner ring road, what were they sniffing?
Note that the M6 was the first motorway, not the M1.
Indeed, it was equal third with the M10 and M45. The M4 Chiswick Flyover opened second (though was signed as A4 at the time)

As Chris says, motorway numbering is completely separate from the all-purpose system. As well as the overview on roads.org.uk, there's an in-depth history told through the words of the very people involved can be found on PM.
It's also worth reiterating that M6 came about because James Drake was fed up of the Ministry dragging its heels on the numbering question so acted unilaterally using the logic that the M6 connected the A6 to the A6 further north. They had to get signs manufactured in mid-1958, and hedged their bets by only putting a motorway number on the two ADS approaching the terminal junctions and Samlesbury interchange. This meant they'd only need to coverplate at most six signs.
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Re: Why are some Motorways numbered similar to A roads the replaced and others not?

Post by NICK 647063 »

LoopyUpholland wrote: Wed Oct 13, 2021 12:26 I would argue that it would be silly for a Motorway as long as the M5 to be M38 instead. I'd probably have also given the M62 a Mx number, given its importance, and that's to say nothing of the M25.
I think we are getting a bit fixated with single digits……. The M25 the busiest motorway in the country is a 2 digit number and totally fine, remember it all comes down to zones, in reality the M5 couldn’t fit in to the zone leaving London so was never going to be used for that, I can live with the M5 as it is and either even if it was the M38 I don’t think that makes it less important! Look at the M25 and M62………. Also remember very few single digit A roads are important these days! The A1, A2 and A3 are very important but the A4, A5 and A6 are not mainly just handling local traffic.
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Re: Why are some Motorways numbered similar to A roads the replaced and others not?

Post by Chris Bertram »

Let's look over the channel. The Paris outer orbital, La Francilienne, is A/N104, the ring road is A86, and the inner ring is simply the Boulevard Péripherique, and doesn't have a number at all.
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Re: Why are some Motorways numbered similar to A roads the replaced and others not?

Post by Vierwielen »

NICK 647063 wrote: Wed Oct 13, 2021 14:56
LoopyUpholland wrote: Wed Oct 13, 2021 12:26 I would argue that it would be silly for a Motorway as long as the M5 to be M38 instead. I'd probably have also given the M62 a Mx number, given its importance, and that's to say nothing of the M25.
I think we are getting a bit fixated with single digits……. The M25 the busiest motorway in the country is a 2 digit number and totally fine, remember it all comes down to zones, in reality the M5 couldn’t fit in to the zone leaving London so was never going to be used for that, I can live with the M5 as it is and either even if it was the M38 I don’t think that makes it less important! Look at the M25 and M62………. Also remember very few single digit A roads are important these days! The A1, A2 and A3 are very important but the A4, A5 and A6 are not mainly just handling local traffic.
Possibly the M25 could have been named the M0. :D
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Re: Why are some Motorways numbered similar to A roads the replaced and others not?

Post by wrinkly »

Bryn666 wrote: Wed Oct 13, 2021 14:36 They had to get signs manufactured in mid-1958, and hedged their bets by only putting a motorway number on the two ADS approaching the terminal junctions and Samlesbury interchange. This meant they'd only need to coverplate at most six signs.
Is that why half-mile and one-mile ADSs don't have forward road numbers?
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Re: Why are some Motorways numbered similar to A roads the replaced and others not?

Post by gepree68 »

Bryn666 wrote: Wed Oct 13, 2021 14:32 *Liverpool-Eccles (M52)
[...]
I can only presume that the M52 vanished quickly, as in 1969's "Motorways" by James Drake construction drawings refer to the M62, M63, and M64 (which was the original M602 number).
[...]
If you travelled east on M52 from Liverpool to today's M60 / M62 / M602 junction, why did they need to come up with a new number (M64) for the motorway east of this junction?

Were there never any plans for M52 all the way from Liverpool to Eccles and Salford (along today's M602)?
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Re: Why are some Motorways numbered similar to A roads the replaced and others not?

Post by Bryn666 »

gepree68 wrote: Fri Oct 15, 2021 07:28
Bryn666 wrote: Wed Oct 13, 2021 14:32 *Liverpool-Eccles (M52)
[...]
I can only presume that the M52 vanished quickly, as in 1969's "Motorways" by James Drake construction drawings refer to the M62, M63, and M64 (which was the original M602 number).
[...]
If you travelled east on M52 from Liverpool to today's M60 / M62 / M602 junction, why did they need to come up with a new number (M64) for the motorway east of this junction?

Were there never any plans for M52 all the way from Liverpool to Eccles and Salford (along today's M602)?
There were, but once the M62 was decided to run to Liverpool instead of Stretford it was changed.
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Re: Why are some Motorways numbered similar to A roads the replaced and others not?

Post by gepree68 »

Bryn666 wrote: Fri Oct 15, 2021 07:29 There were, but once the M62 was decided to run to Liverpool instead of Stretford it was changed.
So the order of events was like this?
2021-10-15 M52 M62.png
2021-10-15 M62 M63 M64.png
2021-10-15 M62 M63 M602.png
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Re: Why are some Motorways numbered similar to A roads the replaced and others not?

Post by wrinkly »

gepree68 wrote: Fri Oct 15, 2021 10:45
Bryn666 wrote: Fri Oct 15, 2021 07:29 There were, but once the M62 was decided to run to Liverpool instead of Stretford it was changed.
So the order of events was like this?
2021-10-15 M52 M62.png 2021-10-15 M62 M63 M64.png 2021-10-15 M62 M63 M602.png
Yes.

I lived in the area at the time and was interested in roads from 1963.

I never heard of the M52 number until decades later, after I joined SABRE. I first heard of the proposed South Lancashire Motorway as a name without knowing a number for it.

Then later I read about the proposed westward re-routing of the M62 and the the proposed introduction of the M63 and M64 numbers, still years before they happened.

When the first section of the M602 was under construction it was known as M64. It only became M602 on completion. The southward M62 continued to be signed as such until the M602 opened despite being shown as M63 earlier on some maps. The actual construction of the westward M62 came last.
Last edited by wrinkly on Fri Oct 15, 2021 11:17, edited 4 times in total.
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Re: Why are some Motorways numbered similar to A roads the replaced and others not?

Post by SBRoxMan »

ajuk wrote: Wed Oct 13, 2021 00:55 So what is going on with the M5? It's out of zone and an obvious number would be the M38 or the M50
Motorways in England and Wales don't follow the same zone rules as A roads. Motorways follow their own zones, so the M5 is completely in the right zone until it crosses the M4
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Re: Why are some Motorways numbered similar to A roads the replaced and others not?

Post by Bryn666 »

wrinkly wrote: Fri Oct 15, 2021 11:02
gepree68 wrote: Fri Oct 15, 2021 10:45
Bryn666 wrote: Fri Oct 15, 2021 07:29 There were, but once the M62 was decided to run to Liverpool instead of Stretford it was changed.
So the order of events was like this?
2021-10-15 M52 M62.png 2021-10-15 M62 M63 M64.png 2021-10-15 M62 M63 M602.png
Yes.

I lived in the area at the time and was interested in roads from 1963.

I never heard of the M52 number until decades later, after I joined SABRE. I first heard of the proposed South Lancashire Motorway as a name without knowing a number for it.

Then later I read about the proposed westward re-routing of the M62 and the the proposed introduction of the M63 and M64 numbers, still years before they happened.

When the first section of the M602 was under construction it was known as M64. It only became M602 on completion. The southward M62 continued to be signed as such until the M602 opened despite being shown as M63 earlier on some maps. The actual construction of the westward M62 came last.
Yes, there were still several patched signs from the original M62 to M63 renumbering in Salford that survived up until the M60 changeover.

The original M602 of course only got as far as Eccles anyway, the eastwards connection to Regent Road was much later.
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Re: Why are some Motorways numbered similar to A roads the replaced and others not?

Post by Steven »

Bryn666 wrote: Fri Oct 15, 2021 11:53 The original M602 of course only got as far as Eccles anyway, the eastwards connection to Regent Road was much later.
Though for clarity, the M52 South Lancashire Motorway was planned to have its eastern terminus on the A56 at a flat roundabout junction; the present A57(M) underpass was a later addition and not part of the original plans.

The M602 to Eccles was just Stage I.
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