Sometimes I’ve seen signs on dual carriageways and motorways that seem to specify a speed limit that’s the same as the national speed
limit (i.e. 60 or 70 mph for most vehicles, depending on the type of road), which seem a bit… pointless? Today I learned why they’re there, and figured I’d share with you!
The first time I saw this sign, on the A1 near Edinburgh, I wondered why it wasn’t just a national speed limit/derestriction sign. Now I know.
To get there, we need a history lesson.
As early as the 1930s, it was becoming clear that Britain might one day need a network of high-speed, motor-vehicle-only roads: motorways. The first experimental part of this
network would be the Preston By-pass1.
Construction halted on several occasions owing to heavy rain, and only six weeks after opening the road needed to be closed for resurfacing after the discovery that water had
penetrated the material.
Construction wouldn’t actually begin until the 1950s, and it wasn’t just the Second World War that got in the way: there was a legislative challenge too.
When the Preston By-pass was first conceived, there was no legal recognition for roads that restricted the types of traffic that were permitted to drive on them. If a public highway
were built, it would have to allow pedestrians, cyclists, and equestrians, which would doubtless undermine the point of the exercise! Before it could be built, the government needed to
pass the Special Roads Act 1949, which enabled the designation of public roads as “special roads”, to which
entry could be limited to certain classes of vehicles2.
The original motorways had to spell out the regulations at their junctions.
If you don’t check your sources carefully when you research the history of special roads, you might be taken in by articles that state that special roads are “now known as motorways”,
which isn’t quite true. All motorways are special roads, by definition, but not all special roads are motorways.
There’s maybe a dozen or more non-motorway special roads, based on research by Pathetic Motorways (whose site was
amazingly informative on this entire subject). They tend to be used in places where something is like a motorway, but can’t quite be a motorway. In Manchester, a
couple of the A57(M)’s sliproads have pedestrian crossings and so have to be designated special roads rather than motorways, for example3.
“…is hereby varied by adding Class IX of the Classes of Traffic set out in Schedule 4 to the Highways Act 1980 as a class of traffic permitted to use those lengths of the special
roads described in the Schedule to this Scheme and which…” /snoring sounds intensify/
Now we know what special roads are, that we might find them all over the place, and that they can superficially look like motorways, let’s talk about speed limits.
The Road Traffic Act 1934 introduced the concept of a 30mph “national speed limit” in built-up areas,
which is still in force today. But outside of urban areas there was no speed limit. Perhaps there didn’t need to be, while cars were still relatively slow, but automobiles
became increasingly powerful. The fastest speed ever legally achieved on a British motorway came in 1964 during a test by AC Cars, when driver Jack Sears reached 185mph.
The “M48” Severn Bridge is another example of a special road that appears to be part of a motorway. The cycle lane and footpath (which is not separated from the main carriageway by
more than a fence) is the giveaway that it’s not truly a “motorway” but a general-case special road.
In the late 1960s an experiment was run in setting a speed limit on motorways of 70mph. Then the experiment was extended. Then the regulation was made permanent.
There’ve been changes since then, e.g. to prohibit HGVs from going faster than 60mph, but fundamentally this is where Britain’s
national speed limit on motorways comes from.
I assume that it relates to the devolution of transport policy or to the separation of legislation that it replaces, but separate-but-fundamentally-identical acts were passed for
Scotland and Northern Ireland.
You’ve probably spotted the quirk already. When “special roads” were created, they didn’t have a speed limit. Some “special roads” were categorised as “motorways”, and “motorways” later
had a speed limit imposed. But there are still a few non-motorway “special roads”!
Putting a national speed limit sign on a special road would be meaningless, because these roads have no centrally-legislated speed limit. So they need a speed limit sign, even
if that sign, confusingly, might specify a speed limit that matches what you’d have expected on such a road4.
That’s the (usual) reason why you sometimes see these surprising signs.
As to why this kind of road are much more-common in Scotland and Wales than they are anywhere else in the UK: that’s a much deeper-dive
that I’ll leave as an exercise for the reader.
Footnotes
1 The Preston By-pass lives on, broadly speaking, as the M6 junctions 29 through 32.
2 There’s little to stop a local authority using the powers of the Special Roads Act and
its successors to declare a special road accessible to some strange and exotic permutation of vehicle classes if they really wanted: e.g. a road could be designated for cyclists and
horses but forbidden to motor vehicles and pedestrians, for example! (I’m moderately confident this has never happened.)
4 An interesting side-effect of these roads might be that speed restrictions based on the
class of your vehicle and the type of road, e.g. 60mph for lorries on motorways, might not be enforceable on special roads. If you wanna try driving your lorry at
70mph on a motorway-like special road with “70” signs, though, you should do your own research first; don’t rely on some idiot from the Internet. I Am Not A Lawyer etc. etc.
Truly in the style and spirit of Challenge Robin / Challenge Robin II, this sweary idiot decides
to try to cross Wales in as close as possible to a completely straight line, cutting through dense woods, farms, rivers, hedgerows and back gardens. Cut up by barbed wire, stung by
nettles, swimming through freezing rivers, and chased by farmers, it makes for gruelling, hilarious watching. Link is to the four-hour playlist; put it on in the background.
It was 1949 when highways officials started to look at traffic issues affecting Newtown.
A multi-million pound bypass that has been 70 years in the planning officially opened in Powys on Thursday.
One haulier said Newtown bypass will make a “big difference” due to
45-minute hold-ups in the town, while the local AM said it was a “momentous” day.
The Welsh Government said the road will ease congestion by about 40% in the town centre.
A public notice printed in 1949 shows a bypass was being considered by the former Montgomeryshire County Council.
The four-mile (6.4km) road runs to the south of the town with two lanes in one direction and one in the opposite direction, to provide overtaking points.
…
Never thought I’d see the day. Back when she used to work in Newtown, Claire would routinely be delayed on her
journey home by traffic passing through the town that could quite-justifiably have gone around it were it not for the lack of a decent trunk road, and she’d bemoan the continuing
absence of the long-promised bypass. That was like 15 years ago… I can’t imagine what it’s been like for the people who’ve lived in Newtown, waiting for the bypass to be built, for
their entire life.
In the time it’s taken to build this bypass, people who’ve been too young to drive have heard about it, grown up, had children of their own, and those people have had children
who are now old enough to drive. The mind boggles.
The unprecedented spell of hot, dry weather across Wales has provided perfect conditions for archaeological aerial photography. As the drought has persisted across Wales, scores of
long-buried archaeological sites have been revealed once again as ‘cropmarks’, or patterns of growth in ripening crops and parched grasslands. The Royal Commission’s aerial
investigator Dr Toby Driver has been busy in the skies across mid and south Wales over the last week documenting known sites in the dry conditions, but also discovering hitherto lost
monuments. With the drought expected to last at least another two weeks Toby will be surveying right across north and south Wales in a light aircraft to permanently record these
discoveries for the National Monuments Record of Wales, before thunderstorms and rain wash away the markings
until the next dry summer.
Claire, Peter and I gatecrashed a friend-of-a-friend’s house party last night, and ate all of their Pringles. One of the housemates’ music collections was fab: all the best of the
Goo Goo Dolls, 3 Doors Down, Nirvana… and some weird (but actually quite good) Welsh rock band.
(Is Welsh Rock a genre? Or just something you buy on the prom at Aberystwyth?)
Must start my Christmas shopping.
[Edit: Came home from the party with an irresistible urge to listen to Pink Floyd’s ‘Comfortably Numb’. Weird.]
This archived blog post has been flagged as containing content that treats or depicts people negatively based on their appearance or identity. This wasn't okay at the time and it
isn't okay now.
I don't believe it's acceptable to pretend I didn't write them by removing them from the Internet - insofar as such a thing is even possible. However, I also don't want to give them
any more visibility than they already have.
Cool And Interesting Thing Of The Day To Do At The University Of Wales, Aberystwyth, #18:
Play drinking games and ‘dare’ in a pub on an Outward Bound weekend… with your lecturer. Laugh as he has to ask the bar staff if they’re virgins, announce he’s gay, and go into the
ladies toilets with his trousers around his ankles. Laugh slightly less when you have to shout “the Welsh are all sheep shaggers” at the top of your voice, and subsequently get lynched.
Ah well: you win some, you lose some.
The ‘cool and interesting things’ were originally published to a location at which my “friends back home” could read them, during the first few months of my time at the University
of Wales, Aberystwyth, which I started in September 1999. It proved to be particularly popular, and so now it is immortalised through the medium of my weblog.
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