Author Topic: Road numbers that don't make sense  (Read 1029 times)

Cudzoziemiec

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Road numbers that don't make sense
« on: February 06, 2020, 10:41:40 am »
Inspired by the "gap" in the A420 between Chippenham and Swindon, as mentioned on the terrifying roads thread and solved by tonyh.
.... And the A420 from Chippenham to Swindon? Doesn't exist. UK road numbers are weird.

(checks on 1947 map....)

That section used to be the A420, but is now A3102 and B4069.
https://yacf.co.uk/forum/index.php?action=post;quote=2463952;topic=9750.150;last_msg=2463955

Then there's the 4040. Is that an A or B road? Take your pick! The B4040 runs from near Chipping Sodbury through Malmesbury to Cricklade (just north of Swindon), while the A4040 is in Birmingham.

There is, of course, a geeky website dedicated to things like this: https://www.sabre-roads.org.uk
Quote
We discuss roads, share information, and arrange meet-ups and road trips around the UK.
Their meet-ups must make an Audax AGM look like a rave.*  :demon:

(They also say that the A4040, now "the former Birmingham outer ring road," used to be a road from Kidderminster to Staffordshire. Weirder and weirder!)

So let's have your roads with gaps in, duplicated numbers, and other oddities.

*I'm sure it was in the Audax board of this august forum that I first heard of SABRE.
I do not ride a great big Mercian, gangster tanwalls, fixed cog in the back.


hellymedic

  • Just do it!
Re: Road numbers that don't make sense
« Reply #2 on: February 06, 2020, 01:42:20 pm »
I've remarked before how the A5 (Watling Street) crosses the A41 in Edgware, Stanmore, and near Newport (Shropshire)...

A40/A4020 Oxford Street/Oxford Road/ Uxbridge Road make sense to me.

Re: Road numbers that don't make sense
« Reply #3 on: February 07, 2020, 12:19:09 pm »
Could go with the A480 being in the Hereford area (link to the A44), but the B480 is Oxford-Henley. Meanwhile, the B4800 resides in Montgomeryshire...

There's also the fact that the A30 "dissapears" at the A303/A34 junction, as it multiplexes with the A303 to the East. Then, the A303 ends at the M3 junction, and the A30 appears out of the aether and carries on! For whatever reason the road with the shorter number is not the main route there...

hellymedic

  • Just do it!
Re: Road numbers that don't make sense
« Reply #4 on: February 07, 2020, 12:57:51 pm »
Watling Street has been renumbered A5183 in Hertfordshire. I'll always think of it as the A5, everywhere.

Re: Road numbers that don't make sense
« Reply #5 on: February 08, 2020, 10:59:44 am »
I've remarked before how the A5 (Watling Street) crosses the A41 in Edgware, Stanmore, and near Newport (Shropshire)...

A40/A4020 Oxford Street/Oxford Road/ Uxbridge Road make sense to me.

The A41 is a serial offender. Just local to me it crosses the A55 then the A56 and the M53.
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Mr Larrington

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Re: Road numbers that don't make sense
« Reply #6 on: February 08, 2020, 12:07:06 pm »
Codesharing among roads seems to be fairly common in USAnia, especially where old Federal highways have been subsumed by the Interstate system.  Which is not immune either; I-80 and I-90 are one and the same for some considerable distance in Ohio and Indiana.  Then you have the odd numbering system used by Interstate spurs such that there are (at least) two entirely separate I-580s.
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Cudzoziemiec

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Re: Road numbers that don't make sense
« Reply #7 on: February 08, 2020, 12:43:18 pm »
"Out of zone" roads make sense, at least where they start (or finish, depending which way you're going) "in zone". But duplicated numbers, like A/B4040 and the A/B480 are harder to explain. I suppose one has been mistakenly renumbered.
I do not ride a great big Mercian, gangster tanwalls, fixed cog in the back.

Re: Road numbers that don't make sense
« Reply #8 on: February 15, 2020, 09:51:54 am »
Codesharing among roads seems to be fairly common in USAnia, especially where old Federal highways have been subsumed by the Interstate system.  Which is not immune either; I-80 and I-90 are one and the same for some considerable distance in Ohio and Indiana.  Then you have the odd numbering system used by Interstate spurs such that there are (at least) two entirely separate I-580s.
I think the numbering system on the spurs takes advantage of the fact that the spurs are usually far enough apart that it doesn't matter if there are more than one with the same number. 
And it seems that the spurs with odd-numbers to start (say, I-105 in Oregon) are dead-ended spurs, while those with even numbers eventually connect back to the "main" road - I-405 east of Seattle, I-205 near Portland, etc.

and of course what is now I-84 used to be I-80N along the Columbia River in Oregon.

I think the doubling-up of I-80/I-90 can be explained by both of them squeezing together south of Lake Michigan and Lake Eire.

Of the numbered "federal" highways, US 20 is rather unique in that it is contiguous.  Most of the other cross-continental routes have gaps, but so far, US-20 doesn't.  At its west end (Newport, Oregon) there's a sign reading "US 20 East - Boston, MA 3,365 miles" .  Not to be mistaken for the 'other' Boston

Mr Larrington

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Re: Road numbers that don't make sense
« Reply #9 on: February 16, 2020, 12:42:24 pm »
Part of me has a hankering to do a US-50 road trip, which is what Bobby Troup almost did before deciding to follow US-66.  And wrote a little ditty about it.

I'm still a bit puzzled about how 50 and US-6 manage to be the same road in eastern NV, mind.
External Transparent Wall Inspection Operative & Mayor of Mortagne-au-Perche
Satisfying the Bloodlust of the Masses in Peacetime

FifeingEejit

  • Not Small
Re: Road numbers that don't make sense
« Reply #10 on: February 16, 2020, 12:59:42 pm »
Then there's the 4040. Is that an A or B road? Take your pick! The B4040 runs from near Chipping Sodbury through Malmesbury to Cricklade (just north of Swindon), while the A4040 is in Birmingham.

The reason for this is that they are road numbers not route numbers, the MoT (as was) when they allocated the numbers of A and B roads could have had a bit more thought about what they were doing right enough.

Something the system for GB did however do was insist that B roads started at 100. The NI numbering system does have single digit B roads.

The only part of GB where there is a resemblance to Route numbers is in Scotland due to the then Scottish office deciding that Motorways would take the number of the road they were bypassing/upgrading. (Roads were devolved to the secretary of state for Scotland in the 1950s)

In England the best example of this is with the A1(M) route and M1 route being completely different on leaving London until they merge at Leeds.

If this approach had been taken in Scotland the M/A74(M), M77 and M73 would have been fighting over the numbers M7, M70 and M71 instead of simply taking the route number.


The NCN numbering system is route based and is completely independent of the road numbering system; hence why the NCN7 north of Perth is known by everyone as "The A9 cycle track"

Cudzoziemiec

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Re: Road numbers that don't make sense
« Reply #11 on: February 16, 2020, 01:36:54 pm »
Then there's the 4040. Is that an A or B road? Take your pick! The B4040 runs from near Chipping Sodbury through Malmesbury to Cricklade (just north of Swindon), while the A4040 is in Birmingham.

The reason for this is that they are road numbers not route numbers, the MoT (as was) when they allocated the numbers of A and B roads could have had a bit more thought about what they were doing right enough.
We could have had a system where A and B numbers were separate and routinely duplicated, as A and M are. I suppose a reason not to do that would be confusion when a road was down- or upgraded; perhaps this possibility was foreseen from the beginning. But as we don't have that system, I reckon one of the duplicates is a mistake.
I do not ride a great big Mercian, gangster tanwalls, fixed cog in the back.

FifeingEejit

  • Not Small
Re: Road numbers that don't make sense
« Reply #12 on: February 16, 2020, 02:01:15 pm »
Then there's the 4040. Is that an A or B road? Take your pick! The B4040 runs from near Chipping Sodbury through Malmesbury to Cricklade (just north of Swindon), while the A4040 is in Birmingham.

The reason for this is that they are road numbers not route numbers, the MoT (as was) when they allocated the numbers of A and B roads could have had a bit more thought about what they were doing right enough.
We could have had a system where A and B numbers were separate and routinely duplicated, as A and M are. I suppose a reason not to do that would be confusion when a road was down- or upgraded; perhaps this possibility was foreseen from the beginning. But as we don't have that system, I reckon one of the duplicates is a mistake.

There's plenty of 3 and 4 digit numbers that are used by both A and B numbers.

The two 4040 numbers have been allocated by the DfT in accordance with their system, it's not a mistake, it's the way the system used in England works that it has M, A and B numbering disconnected by everything other than the Zones; the motorways in England are even on a different zoning system from the A and B zones.

The MoT defined it in the early 1930s after much consideration and argument (this seems to be a recurring theme in the MoT and DfT).

The zoning is explained in: https://en.wikipedia.org/wiki/Great_Britain_road_numbering_scheme
In https://en.wikipedia.org/wiki/A_roads_in_Zone_1_of_the_Great_Britain_numbering_scheme#Triple-digit_roads it looks like almost every 3 digit number used for a B road is also used for an A road.

As another number duplicate example
The A1010 is Tottenham to Walthamcross - Goes North
The B1010 does Woodham Mortimer to Burnham on Crouch - Goes East

Just as different as for the A4040 and B4040

Re: Road numbers that don't make sense
« Reply #13 on: February 21, 2020, 10:17:23 am »
If it wasn't for motor traffic, I'd ride the A361. It'd be a nice route from Banbury to Ilfracombe.
The A50 used to run close to the A5. Starting in Hockliffe IIRC and going up to at least Leicester via Newport Pagnell and Northampton, which is now the B526. I remember the riding the A50 from Northampton to Leicester in the 1990s until the new one got built and Northampto to Leicester got rebranded as the A5199.