Why does the M6 turn into the M74 in Scotland?

[ais523]

However it was not by picking numbers out of a hat that we ended up with the M2, M4, M6, M11, M18, M20, M23, M25 (which originally included what is now the M26), M27, M40, M45, M48, M56, M58 and M62 all to a greater or lesser extent shadowing the corresponding-numbered A roads.

And of course, the M42 acts as a continuation of the A42, but in that case the A-road appears to have been named after the motorway rather than vice versa (it would be unlikely to have been given its out-of-zone number otherwise).

Road numbering in England nowadays appears to be "there were rules once, but nowadays people just give roads numbers that 'feel' right; these often end up following the old rules due to people having subconsciously figured some of the old rules out, but you can't rely on it and a significant portion of road numbers are named after rules that someone made up on the spot". Thus, motorways being named after A-roads (or vice versa) even in England.

There are of course instances of motorway numbers not matching A-road numbers, even when there would be little cost to doing so. For example, the M69 would be more logically numbered M46 (it even extends 100m or so into motorway zone 4, which is more of a justification for an out-of-zone number than some I've seen).

[Cryoraptor]

For example, the M69 would be more logically numbered M46 (it even extends 100m or so into motorway zone 4, which is more of a justification for an out-of-zone number than some I've seen)

Now there's the 'get out of non-zone motorway number' clause I've been looking for!

In all seriousness, not to derail the topic too much, but motorways should be designated based on the A road they act as a replacement for and/or parallel. We wouldn't have the arbitrary, somewhat conjectural motorway number zones and the subsequent nonsensical M5x and M6x designations if that was the case. The original numbering principal for motorways was quite obviously to be whatever all-purpose road they were most related to, as is proved by the (early) M6, M4 and the M1's original number, the 'A50' (which was a reference to the A5, the all-purpose road it replaces for much of the original alignment). Then someone decided that the M38 should be called the M5 and so we got motorway zones. The original principal is still the most logical and so many, I would dare to say most, motorways were numbered in accordance of what A road they replace when they could be. The M2, M4, originally the M6, M8, M9, M11, M20, M25, M40 and so on. Is it so much to ask that the M5 should have been the M38 and the M1 the M5? The M1 starts on a shared junction between the A5 and A406, has more junctions with the A5 than the A1, and originally ended on the A5 before being extended. The M5 is... Well, as much of a motorway parallel of the A38 as the M20 is the A20. It both starts (partially) and ends on the A38, and on the southern end at least, transfers its road to the A38 for it to continue the route into west Devon and Cornwall. I know the excuse is something along the lines of 'M5 is a more important sounding number than M38', but is that really true? The A38 alone is the 3rd longest continuous road in the UK. The number '38' is the 3rd most prestigious designation in the UK, only behind '30' and '1'. Meanwhile, most people have probably never heard of the A5 outside of its local range, or have no idea where it starts or ends. Besides, I don't think anyone would think 'oh, the Birmingham-Exeter motorway doesn't seem as important as the rest because it has a 2-digit designation'. I think most people, especially within its range, would agree that the M20 is a considerably more important route than the neighbouring M2, despite having a 2-digit designation.

Anyway, that's not entirely relevant to the discussion, so I will step off my soapbox now.

EDIT: The A38 is the 2nd longest continuous road. I believe it used to be 3rd until it was extended to Mansfield. If not, I was simply confusing the positions of the A30 and A38

[Big L]

Longest road does not equal most prestigious number.

[trickstat]

Is it so much to ask that the M5 should have been the M38 and the M1 the M5? The M1 starts on a shared junction between the A5 and A406, has more junctions with the A5 than the A1, and originally ended on the A5 before being extended.

Wasn't the M1 from Warwickshire to Yorkshire more of a completion than an extension? I would have thought that the M1 was always intended to be the London-Yorkshire motorway. The A5 doesn't even venture into Northern England let alone Yorkshire.

[trickstat]

The A38 alone is the 3rd longest continuous road in the UK. The number '38' is the 3rd most prestigious designation in the UK, only behind '30' and '1'. Meanwhile, most people have probably never heard of the A5 outside of its local range, or have no idea where it starts or ends.

Some people have heard of the London-Holyhead road and Thomas Telford. That is quite a large local range! Outside of the people on this board and its local range, I suspect not that many people know much about the A38.

[Micro The Maniac]

While some bits of motorway replaces, or bypassed, existing roads, that is not widespread.

[Steven]

There is quite a lot of things here that are, at best, half-truths...

The original numbering principal for motorways was quite obviously to be whatever all-purpose road they were most related to, as is proved by the (early) M6, M4

No, it wasn't at all.

The first motorway numbers were Motor Road project numbers, in which the two mentioned were given the numbers M.2 and M.7 respectively (or MR.2 and MR.7, dependant on the source material).

In addition, it could easily be claimed M6 is closely related to the A45, A34 and A49 for the vast majority of its length and the A6 is totally irrelevant. It's just under 150 miles between Catthorpe and the first point the A6 really becomes vaguely relevant to the M6 near Preston.

Then someone decided that the M38 should be called the M5 and so we got motorway zones.

No, it was never "the M38". It was an idea floated that it might be, but it was never decided that it would be. This sentence is unfortunately very wishful thinking.

The original principal is still the most logical and so many, I would dare to say most, motorways were numbered in accordance of what A road they replace when they could be. The M2, M4, originally the M6, M8, M9, M11, M20, M25, M40 and so on.

Of those, a number are in Scotland which has a different numbering scheme and so is irrelevant to the point unsuccessfully trying to be made.

The M6 is irrelevant to the A6 for most of its length as demonstrated above, and was only numbered that way because James Drake couldn't get an answer out of the Ministry before he needed to get the signs ordered for the Preston Bypass.

The M25, in addition, is totally irrelevant to the A25 for the utter vast majority of its length - they are only anywhere near each other between junctions 5 and 8.

And of course, the point has been totally missed that all of those numbers are valid and in-zone, so why not allocate them if desired?

Is it so much to ask that the M5 should have been the M38 and the M1 the M5?

Yes. It's wishful thinking.

The M1 starts on a shared junction between the A5 and A406, has more junctions with the A5 than the A1, and originally ended on the A5 before being extended.

No. The London - Yorkshire Motorway at the time of numbering being allocated was intended to end at the northern end of the Doncaster Bypass. The southern terminus at Staples Corner was not intended to be that.

The M5 is... Well, as much of a motorway parallel of the A38 as the M20 is the A20. It both starts (partially) and ends on the A38

No, it doesn't. The northern end is on the M6 and it doesn't meet the A38 until junction 4.

and on the southern end at least, transfers its road to the A38 for it to continue the route into west Devon and Cornwall.

And the A30, and the A380...

I know the excuse is something along the lines of 'M5 is a more important sounding number than M38', but is that really true? The A38 alone is the 3rd longest continuous road in the UK. The number '38' is the 3rd most prestigious designation in the UK, only behind '30' and '1'. Meanwhile, most people have probably never heard of the A5 outside of its local range, or have no idea where it starts or ends.

Really? That's a very southern idea. Most people have no clue where the A30 is at all; and many people who live on the A38 are aware of "their" section, but have no clue anywhere else. And its a particular strange example you've chosen there - a road that is in London, travels near to a number of large towns and cities such Milton Keynes, Northampton, Leicester, Coventry, Birmingham, Wolverhampton and Telford isn't "well known". If you'd said something like the A37, then maybe, but...

Besides, I don't think anyone would think 'oh, the Birmingham-Exeter motorway doesn't seem as important as the rest because it has a 2-digit designation'. I think most people, especially within its range, would agree that the M20 is a considerably more important route than the neighbouring M2, despite having a 2-digit designation.

Unfortunately, the point regarding the numbering scheme has been lost; and besides at the time of creation the motorway was proposed to end at Bristol.

[chaseracer]

Some people have heard of the London-Holyhead road and Thomas Telford.

Through a fair chunk of the Midlands, Telford's road became the A41.

[orudge]

It doesn't stay as the M6 because the Scottish government doesn't want it to.

I think the issue is not so much that they don’t want it to, but that they just don’t care sufficiently to do anything about it. It would hardly be a justified use of public funds these days to spend thousands on new signs for very little apparent benefit.

I wouldn't be surprised if they started trying to get the A1 and other such cross-border roads renumbered past the border at some point.

Again, what benefit would there be in doing this? I imagine many voters would rather see a dualled A1 to the border rather than the road being arbitrarily renamed!

[Glenn A]

The M69 was probably the biggest oddity to me. It was 200 miles from the A69 and replaced the A47 between Coventry and Leicester. I know it branched off from the M6, which could explain the 6 in the number, but it remains a complete oddity.

[Steven]

The M69 was probably the biggest oddity to me. It was 200 miles from the A69 and replaced the A47 between Coventry and Leicester. I know it branched off from the M6, which could explain the 6 in the number, but it remains a complete oddity.

It's not even slightly odd and is completely correct, no matter how many times people claim otherwise.

Once again, the motorway zones are nothing to do with the all-purpose zones.

[Bryn666]

The M69 was probably the biggest oddity to me. It was 200 miles from the A69 and replaced the A47 between Coventry and Leicester. I know it branched off from the M6, which could explain the 6 in the number, but it remains a complete oddity.

It's not even slightly odd and is completely correct, no matter how many times people claim otherwise.

Once again, the motorway zones are nothing to do with the all-purpose zones.

The answers are there if people bother to look. I had rather hoped that motorway numbering had gone beyond the "wild mass guessing" phase given the amount of archive raiding numerous individuals have done.

The M69 is the M69 because it's in the motorway 6 zone, and it directly replaces the A46 not the A47.

[KeithW]

And of course, the M42 acts as a continuation of the A42, but in that case the A-road appears to have been named after the motorway rather than vice versa (it would be unlikely to have been given its out-of-zone number otherwise).

Road numbering in England nowadays appears to be "there were rules once, but nowadays people just give roads numbers that 'feel' right; these often end up following the old rules due to people having subconsciously figured some of the old rules out, but you can't rely on it and a significant portion of road numbers are named after rules that someone made up on the spot". Thus, motorways being named after A-roads (or vice versa) even in England.

There are of course instances of motorway numbers not matching A-road numbers, even when there would be little cost to doing so. For example, the M69 would be more logically numbered M46 (it even extends 100m or so into motorway zone 4, which is more of a justification for an out-of-zone number than some I've seen).

As I recall it was rather simpler than that. The original section was built in the 1970's as a motorway spur from the M40 to service the NEC. In the 1980's it was was decided to build an extension to provide to provide a link from Birmingham to the M1 at Nottingham. They ran out of money and had to downgrade the last section to the M1 to an all purpose D2 to complete it.

[Bryn666]

The original M42 line of course was rather different but financial and environmental considerations resulted in the slapdash half effort to connect Ashby to the M1.

Twas ever thus, big plans in the UK usually end the same way; in a giant shredder unless a prominent local MP happens to be backing it.

[Steven]

As I recall it was rather simpler than that. The original section was built in the 1970's as a motorway spur from the M40 to service the NEC. In the 1980's it was was decided to build an extension to provide to provide a link from Birmingham to the M1 at Nottingham. They ran out of money and had to downgrade the last section to the M1 to an all purpose D2 to complete it.

Not quite. The M42 Castle Donington Section from the present northern terminus to Stanton-by-Dale was part of the 1970s plan, but was first re-routed east of Castle Donington in March 1976, before being downgraded to an all-purpose proposal in 1982.

[Glenn A]

The M69 was probably the biggest oddity to me. It was 200 miles from the A69 and replaced the A47 between Coventry and Leicester. I know it branched off from the M6, which could explain the 6 in the number, but it remains a complete oddity.

It's not even slightly odd and is completely correct, no matter how many times people claim otherwise.

Once again, the motorway zones are nothing to do with the all-purpose zones.

The answers are there if people bother to look. I had rather hoped that motorway numbering had gone beyond the "wild mass guessing" phase given the amount of archive raiding numerous individuals have done.

The M69 is the M69 because it's in the motorway 6 zone, and it directly replaces the A46 not the A47.

Yes A47, and regardless of its number, a very useful motorway that slashed journey times between Coventry and Leicester and linked Coventry to the northbound M1 by motorway.

[Chris Bertram]

It's not even slightly odd and is completely correct, no matter how many times people claim otherwise.

Once again, the motorway zones are nothing to do with the all-purpose zones.

The answers are there if people bother to look. I had rather hoped that motorway numbering had gone beyond the "wild mass guessing" phase given the amount of archive raiding numerous individuals have done.

The M69 is the M69 because it's in the motorway 6 zone, and it directly replaces the A46 not the A47.

Yes A47, and regardless of its number, a very useful motorway that slashed journey times between Coventry and Leicester and linked Coventry to the northbound M1 by motorway.

To be fair, it's a direct replacement for A46, and also relieves A47 between Hinckley and Leicester.

[Chris5156]

The A38 alone is the 3rd longest continuous road in the UK. The number '38' is the 3rd most prestigious designation in the UK, only behind '30' and '1'. Meanwhile, most people have probably never heard of the A5 outside of its local range, or have no idea where it starts or ends.

If the A5 is such an obscure number undeserving of having a motorway named after it, why do you want to name the M1 after it?

[Micro The Maniac]

The M69 was probably the biggest oddity to me. It was 200 miles from the A69 and replaced the A47 between Coventry and Leicester. I know it branched off from the M6, which could explain the 6 in the number, but it remains a complete oddity.

It's not even slightly odd and is completely correct, no matter how many times people claim otherwise.

Once again, the motorway zones are nothing to do with the all-purpose zones.

The M69 starts *south* of the M6, and therefore (should be) in Motorway Zone 4

[Chris5156]

The M69 was probably the biggest oddity to me. It was 200 miles from the A69 and replaced the A47 between Coventry and Leicester. I know it branched off from the M6, which could explain the 6 in the number, but it remains a complete oddity.

It's not even slightly odd and is completely correct, no matter how many times people claim otherwise.

The M69 starts *south* of the M6, and therefore (should be) in Motorway Zone 4

It extends about 600m south of the M6 out of necessity, simply because motorway regulations start and end where the south-facing sliproads from the interchange meet it. I don't think you could say with a straight face that the M69 motorway continues its journey south of Ansty Interchange - the end of the route is at its junction with the M6, whatever the details of how the sliproads and carriageways interact!

By the same logic you could argue that the M18 should have a 6-zone number because the northbound carriageway runs west of the M1 for 500 metres at Thurcroft Interchange, or that the M61 ought to be in the 5-zone because its northbound side strays west of the M6 at its terminus.