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

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

Post by Glenn A » Sun Oct 17, 2021 11:40

There is a myth that the M6 replaced the A6 from Carlisle to London, and that before the M6, everyone travelled to London from Cumbria and Lancashire on the A6. The M6 only replaced the A6 from Preston to Carlisle, and using the A6 to get to London in the pre motorway era would be a very tedious drive that would involve driving through Manchester and the East Midlands. Also the M6 south of Preston veers a large distance from the A6.

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

Post by KeithW » Sun Oct 17, 2021 13:35

Glenn A wrote:
Sun Oct 17, 2021 11:40
There is a myth that the M6 replaced the A6 from Carlisle to London, and that before the M6, everyone travelled to London from Cumbria and Lancashire on the A6. The M6 only replaced the A6 from Preston to Carlisle, and using the A6 to get to London in the pre motorway era would be a very tedious drive that would involve driving through Manchester and the East Midlands. Also the M6 south of Preston veers a large distance from the A6.
Well lets address this myth.

The reality is that pre WW2 the main way people travelled from London to Carlisle was by rail. That is hardly relevant however as the the origins of the M6 lie in a study produced by the University of Birmingham entitled The London-Birmingham Motorway published by HM Stationery Office in 1960. Cars had become important for shorter distances but on long haul it took the opening of the motorways to make it a viable option.

I was born in 1952 and as a child we went on holidays to Kent, East Anglia, the Yorkshire Coast and Lincolnshire. Most of those trips were by train. In the street where we lived there were 12 houses and only 4 had cars, mostly used for travelling to and from work. An Austin A35 or sits up and beg Ford Popular was hardly a motorway cruiser. My dad had been a driver in WW2 but never owned a car. It wasnt until about 1968 when the A1/M1 largely opened that road transport became a viable option for long haul. Even then anywhere south of London was a pain and as for Devon and Cornwall that was a nightmare journey. In the early 1970's we always planned on the basis of leaving Teesside at about teatime and taking an overnight stop near Derby before hitting the A38 at the crack of dawn.

Turning to the London-Birmingham route he reality is that there were 3 primary routes used by road traffic at the time of the study, the A5/A45, the A41 and the A40. To a large extent the choice of route depended on where in London you were starting from and which part of the West Midlands you were aiming for. If you were headed towards Carlisle then the A5/A51 would probably be favourite as the by the standards of the day the Coventry bypass was about as good as it got.

Average speeds were low, surveys on the A5/A45 route gave 35 mph for cars, 31 for light goods vehicles and 26 mph for HGV's. The crossover point where most travel started to be road was around 1957 but over long distances such as London to Carlisle driving would still be a long and tedious business. I recall the pre M6 route over Shap Fell, fun it was not even in summer.

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

Post by wrinkly » Sun Oct 17, 2021 17:21

KeithW wrote:
Sun Oct 17, 2021 13:35
the the origins of the M6 lie in a study produced by the University of Birmingham entitled The London-Birmingham Motorway published by HM Stationery Office in 1960.
That can't be true. The Thelwall and Gathurst viaducts started construction in 1959, and the orders for some other sections must have been in place before 1960. The Stafford bypass opened in 1962 and there was a continuous motorway from north of Preston to south of Stafford by 1963.
Last edited by wrinkly on Sun Oct 17, 2021 18:04, edited 1 time in total.

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

Post by Glenn A » Sun Oct 17, 2021 17:28

KeithW wrote:
Sun Oct 17, 2021 13:35
Glenn A wrote:
Sun Oct 17, 2021 11:40
There is a myth that the M6 replaced the A6 from Carlisle to London, and that before the M6, everyone travelled to London from Cumbria and Lancashire on the A6. The M6 only replaced the A6 from Preston to Carlisle, and using the A6 to get to London in the pre motorway era would be a very tedious drive that would involve driving through Manchester and the East Midlands. Also the M6 south of Preston veers a large distance from the A6.
Well lets address this myth.

The reality is that pre WW2 the main way people travelled from London to Carlisle was by rail. That is hardly relevant however as the the origins of the M6 lie in a study produced by the University of Birmingham entitled The London-Birmingham Motorway published by HM Stationery Office in 1960. Cars had become important for shorter distances but on long haul it took the opening of the motorways to make it a viable option.

I was born in 1952 and as a child we went on holidays to Kent, East Anglia, the Yorkshire Coast and Lincolnshire. Most of those trips were by train. In the street where we lived there were 12 houses and only 4 had cars, mostly used for travelling to and from work. An Austin A35 or sits up and beg Ford Popular was hardly a motorway cruiser. My dad had been a driver in WW2 but never owned a car. It wasnt until about 1968 when the A1/M1 largely opened that road transport became a viable option for long haul. Even then anywhere south of London was a pain and as for Devon and Cornwall that was a nightmare journey. In the early 1970's we always planned on the basis of leaving Teesside at about teatime and taking an overnight stop near Derby before hitting the A38 at the crack of dawn.

Turning to the London-Birmingham route he reality is that there were 3 primary routes used by road traffic at the time of the study, the A5/A45, the A41 and the A40. To a large extent the choice of route depended on where in London you were starting from and which part of the West Midlands you were aiming for. If you were headed towards Carlisle then the A5/A51 would probably be favourite as the by the standards of the day the Coventry bypass was about as good as it got.

Average speeds were low, surveys on the A5/A45 route gave 35 mph for cars, 31 for light goods vehicles and 26 mph for HGV's. The crossover point where most travel started to be road was around 1957 but over long distances such as London to Carlisle driving would still be a long and tedious business. I recall the pre M6 route over Shap Fell, fun it was not even in summer.
The other alternative was A6/A66/A1, but both routes were tedious and slow and in winter the A66 could be blocked at Stainmore, same as the A6 at Shap. Obviously far fewer people drove then, but people who owned cars and needed to travel to London, a long slog of a journey awaited and, of course, there was the possibility of a breakdown.

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

Post by Steven » Sun Oct 17, 2021 18:14

wrinkly wrote:
Sun Oct 17, 2021 17:21
KeithW wrote:
Sun Oct 17, 2021 13:35
the the origins of the M6 lie in a study produced by the University of Birmingham entitled The London-Birmingham Motorway published by HM Stationery Office in 1960.
That can't be true. The Thelwall and Gathurst viaducts started construction in 1959, and the orders for some other sections must have been in place before 1960. The Stafford bypass opened in 1962 and there was a continuous motorway from north of Preston to south of Stafford by 1963.
It's not unfortunately.

The Northern and Western Motorway of 1923 was probably the earliest concept of the proposal that finally became the M1 and M6 from London to Lancashire; followed by the 1929 Birmingham - Manchester Motorway. In 1938, Leslie Hore-Belisha recommended approval of the Lancashire North-South Motorway, though clearly WW2 got in the way; whilst in the same year the County Surveyors proposed a motorway network which basically resurrected the Northern and Western Motorway. Then there's the 1949 Road Plan for Lancashire etc etc etc.

The potentially confusing part is that for quite some time the West Midlands - Lancashire stretch was thought of as one route, and the Midlands Links thought of as separate.

It's also worth remember that the original plan for the M45 was that it should be the start of the Midlands Links, although that had changed to the present route north of Coventry prior to construction.
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Re: Why are some Motorways numbered similar to A roads the replaced and others not?

Post by JohnnyMo » Sun Oct 17, 2021 19:11

wrinkly wrote:
Sun Oct 17, 2021 17:21
KeithW wrote:
Sun Oct 17, 2021 13:35
the the origins of the M6 lie in a study produced by the University of Birmingham entitled The London-Birmingham Motorway published by HM Stationery Office in 1960.
That can't be true. The Thelwall and Gathurst viaducts started construction in 1959, and the orders for some other sections must have been in place before 1960. The Stafford bypass opened in 1962 and there was a continuous motorway from north of Preston to south of Stafford by 1963.
A lot of motorway studies were published with various names,
London -Yorkshire motorway is what is now the M1 well sort of.
Birmingham - Preston, this was amalgamated into the Lancaster - Bristol (?) motorway.
A separate link motorway as planned to join the London -Yorkshire and Lancaster - Bristol.

I assume the London-Birmingham Motorway is what we now call the M40
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Re: Why are some Motorways numbered similar to A roads the replaced and others not?

Post by KeithW » Sun Oct 17, 2021 20:23

wrinkly wrote:
Sun Oct 17, 2021 17:21
KeithW wrote:
Sun Oct 17, 2021 13:35
the the origins of the M6 lie in a study produced by the University of Birmingham entitled The London-Birmingham Motorway published by HM Stationery Office in 1960.
That can't be true. The Thelwall and Gathurst viaducts started construction in 1959, and the orders for some other sections must have been in place before 1960. The Stafford bypass opened in 1962 and there was a continuous motorway from north of Preston to south of Stafford by 1963.
Note I said published in 1960 and I can send you a pdf copy to prove it, Clearly the research predates the publication, in fact here is the references section
(1) Charlesworth, G., and T. M. Coburn. The influence of road layout on speeds
and accidents in rural areas. Publ. Wks munic. Services Congr., 1956. Final report,
308-28 ; Discussion, 374-80.
(2) Wardrop, J. G. Some theoretical aspects of road traffic research. Proc. Instn civ.
Engrs, Part II. 1952, 1(2), 325-62; Discussion, 362-78.
(3) Highway Research Board. Traffic assignment. Bulletin 61 : Washington, D.C.,
1952 (National Research Council, Division of Engineering and Industrial
Research).
(4) Mortimer, W. I. Expressway influence on parallel routes. A study of Edens
Expressway traffic diversion and generation trends. Chicago, Illinois, 1955 (Cook
County Highway Department).
(5) Smeed, R, J. Road design in relation to traffic movement and road safety. J. Instn
munic. Engrs, 1954, 81(3), 129-43.
(6) Glanville, W. Ii, and R. J. Smeed. The basic requirements for the roads of
Great Britain. Conference on the Highway Needs of Great Britain, 1957, Proceedings.
London, 1958. (Institution of Civil Engineers), pp. 17-53; Discussion, 53-68.
(7) Ministry of Labour. Ministry of Labour Gazette. London, 1957 (H.M. Stationery
Office).
(8) Glover, K. F., and D. N. Miller. The outlines of the road goods transport
industry. J. roy. statist. Soc., Series A {General), 1954, 117(3), 297-323 ; Discussion
324-30.
(9) Commercial Motor. Tables of operating costs for all types of commercial vehicle.
London, 1957 (Temple Press, Ltd.), 42nd Edition.
(10) Anon. British built for world markets: major details of specification and performance.
Autocar, 1957, 106(3206), 764-7.
(11) Reynolds, D. J. The effect of road conditions on fuel consumption. Department
of Scientific and Industrial Research, Road Research Laboratory Note No. RN
/
2883/DJR. Harmondsworth, 1956 (Unpublished).
(12) Moyer, R. A., and G. L. Tesdell. Tyre wear and cost on selected roadway
surfaces. Iowa State College, Engineering Experiment Station, Bulletin 161 : Ames,
Iowa, 1945 (Iowa State College).
(13) Gough, V. E., J. H. Hardman and J. R. MacClaren. Abraded tyre treads.
l.R.I. Transactions, 1956, 32(2), 27-49; Discussion 50-4.
(14) Saal, C. C. Operating characteristics of a passenger car on selected routes.
Publ. Rds, Wash., 1955, 28(9), 179-201.
(15) Cree, J. C., and J. G. Withers. All-season high performance oil. Successful
developments at the Sunbury Research Station. Auto. Engr, 1955, 45(1), 21-8.
(16) Reynolds, D. J. The cost of road accidents. J. roy. statist. Soc., Series A (General),
1956, 119(4), 393-408,
(17) Minister of Transport and Civil Aviation. Roads in England and Wales.
Report for the year 1957-58. London, 1958 (H.M. Stationery Office), p. 36.
(18) Schmidt, R. E., and M. E. Campbell. Highway traffic estimation. Saugatuck,
Connecticut, 1956 (Eno Foundation for Highway Traffic Control).
(19) Anon. Competition in the car market. Economist, 1957, 185(5956), Supplement
12-3.
Anon. Motoring for the million. Economist, 1954, 173(5800), Supplement, 12-3.
(20) Anon. British funds and guaranteed stocks. Economist, 1958, 189(6006), 84.

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

Post by KeithW » Sun Oct 17, 2021 20:39

JohnnyMo wrote:
Sun Oct 17, 2021 19:11


A lot of motorway studies were published with various names,
London -Yorkshire motorway is what is now the M1 well sort of.
Birmingham - Preston, this was amalgamated into the Lancaster - Bristol (?) motorway.
A separate link motorway as planned to join the London -Yorkshire and Lancaster - Bristol.

I assume the London-Birmingham Motorway is what we now call the M40
That would be incorrect. The route was Watford, Luton, Newport Pagnell, Northampton, Daventry. It was in fact what became the M1, M10 and M45

There are two such studies on the US Internet Archive
The London to Birmingham Motorway
https://archive.org/details/op1265813-1001

The London to Yorkshire Motorway
https://archive.org/details/op1265812-1001

This was the second section that followed on from The London to Birmingham Motorway. At the time the study was made no designation for the new road had been finalised

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

Post by Vierwielen » Sun Oct 17, 2021 22:02

Chris5156 wrote:
Sat Oct 16, 2021 16:38
Vierwielen wrote:
Sat Oct 16, 2021 09:47
So if we were to adopt that custom, the M25 would be the R0(M), the M60 would be the R1(M) and the M42/M6(toll)/A460/A449/A491/A38 would be the R2, R2(M) or R2(T) depending on the type of road.
In what world is that collection of roads considered to function as a single ring road? :shock:
I assume that you are talking about the West Midlands collection of roads. The M42 forms the southern and eastern parts of the ring, the M6(toll) the northern part of the ring and the A460/A449/A491/A38 wishful thinking for the western part of the ring (if they were linked up in a sensible manner to allow traffic between the South West and the North West to by-pass the West Midlands.
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Re: Why are some Motorways numbered similar to A roads the replaced and others not?

Post by Vierwielen » Sun Oct 17, 2021 22:05

Bryn666 wrote:
Sat Oct 16, 2021 17:09
Chris5156 wrote:
Sat Oct 16, 2021 16:38
Vierwielen wrote:
Sat Oct 16, 2021 09:47
So if we were to adopt that custom, the M25 would be the R0(M), the M60 would be the R1(M) and the M42/M6(toll)/A460/A449/A491/A38 would be the R2, R2(M) or R2(T) depending on the type of road.
In what world is that collection of roads considered to function as a single ring road? :shock:
It wouldn't. In Belgium R routes are often not full rings. Antwerp is a good example where R2 is a corner cut and nothing else.
If one considers the M25 as the outer ring road of London, one could, with a bit of imagination, consider the A34, the Oxford-Cambridge Expressway ( :pig: ) and the A14 as an incomplete further ring road of London (or the South East!).

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

Post by Steven » Sun Oct 17, 2021 22:09

Vierwielen wrote:
Sun Oct 17, 2021 22:02
Chris5156 wrote:
Sat Oct 16, 2021 16:38
Vierwielen wrote:
Sat Oct 16, 2021 09:47
So if we were to adopt that custom, the M25 would be the R0(M), the M60 would be the R1(M) and the M42/M6(toll)/A460/A449/A491/A38 would be the R2, R2(M) or R2(T) depending on the type of road.
In what world is that collection of roads considered to function as a single ring road? :shock:
I assume that you are talking about the West Midlands collection of roads. The M42 forms the southern and western parts of the ring, the M6(toll) the northern part of the ring and the A460/A449/A491/A38 wishful thinking for the western part of the ring (if they were linked up in a sensible manner to allow traffic between the South West and the North West to by-pass the West Midlands.
Except they don't - as pointed out this idea would send through traffic directly into an important city centre so would be an appalling idea for a bypass or ring road.

It also makes the classic mistake of thinking that the West Midlands is a monolithic entity with a single functional area and is all focussed on Birmingham.

Schoolboy errors both. There's a reason why the M6 Toll, M42 and Western Orbital were all planned as entirely separate projects.
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Re: Why are some Motorways numbered similar to A roads the replaced and others not?

Post by wrinkly » Mon Oct 18, 2021 00:07

KeithW wrote:
Sun Oct 17, 2021 20:39

There are two such studies on the US Internet Archive
The London to Birmingham Motorway
https://archive.org/details/op1265813-1001

The London to Yorkshire Motorway
https://archive.org/details/op1265812-1001

This was the second section that followed on from The London to Birmingham Motorway. At the time the study was made no designation for the new road had been finalised
Thank you for these links. Lots of good stuff in these documents, especially the second. Page 21 of the second document is headed "ROUTE NUMBERING OF MOTORWAYS" and contains two references to the M6:
M.5 will be reserved for the Bristol-Birmingham Motorway, M.6 for the Penrith-Birmingham Motorway (and its eventual extension to join the London-Yorkshire Motorway north of Crick).
and
Preston By-pass Motorway, which has been known since it was opened as Route M.6, will retain that number.
I assume that is what you meant when you said that "the origins of the M6 lie in" this study.

However, as the quotes make clear, both the plan for a motorway from Birmingham to beyond Lancaster, and the use of the name M6 for the part of it that was already open, both existed already.

This second document is produced by the MoT and seems to be quite separate from the document at the first link, in which I have not yet found anything relevant to either the planning or numbering of the M6.

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

Post by Bryn666 » Mon Oct 18, 2021 08:56

Steven wrote:
Sun Oct 17, 2021 18:14
wrinkly wrote:
Sun Oct 17, 2021 17:21
KeithW wrote:
Sun Oct 17, 2021 13:35
the the origins of the M6 lie in a study produced by the University of Birmingham entitled The London-Birmingham Motorway published by HM Stationery Office in 1960.
That can't be true. The Thelwall and Gathurst viaducts started construction in 1959, and the orders for some other sections must have been in place before 1960. The Stafford bypass opened in 1962 and there was a continuous motorway from north of Preston to south of Stafford by 1963.
It's not unfortunately.

The Northern and Western Motorway of 1923 was probably the earliest concept of the proposal that finally became the M1 and M6 from London to Lancashire; followed by the 1929 Birmingham - Manchester Motorway. In 1938, Leslie Hore-Belisha recommended approval of the Lancashire North-South Motorway, though clearly WW2 got in the way; whilst in the same year the County Surveyors proposed a motorway network which basically resurrected the Northern and Western Motorway. Then there's the 1949 Road Plan for Lancashire etc etc etc.

The potentially confusing part is that for quite some time the West Midlands - Lancashire stretch was thought of as one route, and the Midlands Links thought of as separate.

It's also worth remember that the original plan for the M45 was that it should be the start of the Midlands Links, although that had changed to the present route north of Coventry prior to construction.
Don't forget the extremely short lived consideration of the M6 through Lancs being built as a toll road in the early 1950s. James Drake had, after the war, visited Pennsylvania and New Jersey to examine the 1940 PA Turnpike (now parts of Interstate 70/76/276) and the 1953 New Jersey Turnpike (now partially Interstate 95). This was seen as a way to get more motorway miles built quicker, but the trade-off would be loss of utility as junctions would be further apart and relief for substandard sections of, say, the A49 would mean you'd need to build two new roads instead of one, which is basically what's happened in New Jersey where Interstate 295 runs adjacent to the NJ Turnpike.
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Why is the M1 called the M1?

Post by qwertyK » Mon Oct 18, 2021 13:35

From a road zone numbering perspective, it makes virtually no sense. Whilst it starts in the eastern part of the country where zone 1 is, in the part of London it is in, most roads are in Zone 5 or 4. For a large part of its length, the M1 runs parallel to the A5. I understand that it eventually connects to the A1(M) and runs to the west of the A1, but by some distance. So why is the M1 called the M1? Surely M5 would be a more appropriate number?

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Re: Why is the M1 called the M1?

Post by Steven » Mon Oct 18, 2021 14:41

Motorways have a different numbering scheme in England and Wales to the all-purpose network; hence the zones mentioned are irrelevant.

Motorways have their own zoning system.

See PM for more details, and why the M1 is called that.
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Re: Why is the M1 called the M1?

Post by Micro The Maniac » Tue Oct 19, 2021 09:20

qwertyK wrote:
Mon Oct 18, 2021 13:35
For a large part of its length, the M1 runs parallel to the A5.
For its first 65 miles, the M1 loosely follows the A5... but for its remainder 135 miles it doesn't... so a third which is not "a large part"

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

Post by Bryn666 » Tue Oct 19, 2021 09:31

Where does this continued myth that motorways need to match A roads keep coming from?

It's a separate system of roads. It therefore makes sense to have separate numbers, this is why the US grids work in mirror image of each other so you don't get I-90 and US-90 next to each other - indeed one is right up against the northern edge and the other the southern edge (although this system does break down in the middle, which is why there's still no I-50 or I-60).
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Re: Why is the M1 called the M1?

Post by qwertyK » Tue Oct 19, 2021 10:42

Micro The Maniac wrote:
Tue Oct 19, 2021 09:20
qwertyK wrote:
Mon Oct 18, 2021 13:35
For a large part of its length, the M1 runs parallel to the A5.
For its first 65 miles, the M1 loosely follows the A5... but for its remainder 135 miles it doesn't... so a third which is not "a large part"
A third is relatively significant IMO.
If the motorway numbering system is different to the A road numbering system, why does the M11 run parallel to the old A11 for most of its length? Or the M20 with the A20 etc? M23/A23?

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Re: Why is the M1 called the M1?

Post by Steven » Tue Oct 19, 2021 10:43

qwertyK wrote:
Tue Oct 19, 2021 10:42
If the motorway numbering system is different to the A road numbering system, why does the M11 run parallel to the old A11 for most of its length? Or the M20 with the A20 etc? M23/A23?
If you read the link I posted, then all the information is in there, all taken from the National Archives.

However, the direct answer is because they are valid numbers within the scheme, so they can.
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Re: Why is the M1 called the M1?

Post by Herned » Tue Oct 19, 2021 10:54

qwertyK wrote:
Tue Oct 19, 2021 10:42
A third is relatively significant IMO.
If the motorway numbering system is different to the A road numbering system, why does the M11 run parallel to the old A11 for most of its length? Or the M20 with the A20 etc? M23/A23?
I suspect the answer is because even though it is a separate system, the logic is the same. The (English) numbering is based on London, and the most important road is numbered 1 in both systems. Then logically you can either number clockwise or anti-clockwise, and that decision gets you pretty quickly to the numbering system there is. The first motorway east of the M1 is the M10, the second is the M11. As it was decided not to build an entirely new motorway up the A1 corridor, the next long distance route is towards Cambridge.... and so on. I guess logically that would have led to the M23 perhaps being the M21, but there is enough leeway and common sense to number it the same as the a-road it partially replaces. I guess the truth is it is not a purely rule-based system and common sense does come into it

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