Its first section opened in 1973, and the rest was all built in some form. But the A41(M) doesn't exist. It was canned in favour of orbital roadbuilding, and later resurrected in a more modest guise.
The A41 may not be one of London's major approaches, but that doesn't mean it's a backwater. In the 1920s the whole length from Golders Green to north of Watford was bypassed with 14 miles of new Arterial Road, variously known as Watford Way or the Watford By-Pass Road.
In the years after the Second World War, it was the road north of there that had become the problem. Plodding through a virtually continuous string of towns and villages, the A41 through Hertfordshire was a tedious journey made worse by heavy traffic.
Initially, bypasses were proposed to make a series of hops around King's Langley, Bourne End, Berkhamsted and Tring. By the late sixties the bright idea of joining them up to form a single new road was introduced, bypassing the lot, and in 1971 it was unveiled as the A41(M) Watford-Tring Motorway. One part was built, the Tring Bypass, opening in 1973.
There was no doubt that the A41 needed bypassing. But it wasn't important enough, and didn't need it badly enough, for it to ever be the top priority. There was dithering about whether motorway status was worth the expense. And then, in 1973, the Layfield Report caused the Government to abandon most of their plans for roads in London, and everything changed.
The A41(M) was many things in its short life, but it was categorically nothing to do with the M41 West Cross Route. Though it's often been claimed (and even published in books), the A41(M) Tring Bypass was never going to connect with the M41. The story - which claims the M41 was supposed to be extended north to Birmingham via Tring - originated in an unsubstantiated Usenet post in 1999. It has no basis in fact.
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This description begins at the southeastern end of the route and travels northwest.
Watford to Hemel Hempstead
The A41 runs from Central London (Baker Street, in fact) to Birkenhead. The section we're interested in, proposed to form a new London radial motorway, is between Watford and Tring in Hertfordshire. That new road would begin at Berrygrove Interchange, present-day junction 5 of the M1.
The final intended layout of this junction may be exactly as built, but hints have turned up in some planning documents that suggest an ambitious rebuild, providing a free-flowing through route between the M1 to the south and the A41 to the north.
From there the A41 would form a fast two-lane dual carriageway through the suburbs of Watford. There's some evidence to suggest that this section would have become a motorway, part of the A41(M), with the road listed under that number in a couple of lists of future road projects, but other evidence suggests that a motorway upgrade was off the cards. An interchange at Courtlands Avenue would provide a connection with the Ringway 4 North Orbital Road, and then a much wider A41 would travel the short distance down the hill to Hunton Bridge.
The present-day roundabout was, apparently, laid out as the first stage of an eventual three-level junction, though its final intended layout is not known. It's likely the A41 would have passed over the top of the roundabout uninterrupted, with free-flowing links to the M25 Ringway 4 Western Section. Beyond this point, the road would be the A41(M), a brand new motorway to the west of the old A41.
Bypassing Hunton Bridge to the west, the motorway would then join the line of the present-day A41 Kings Langley Bypass, a dual carriageway built in the early 1990s on roughly the line of the motorway route. An interchange at Two Waters would serve a spur road to Hemel Hempstead. The route would then turn north-west alongside the railway to another junction at Bourne End.
Beyond Bourne End, the motorway would continue out to Hertfordshire on approximately the line of the modern A41, passing Berkhamsted to the west and Tring to the south.
In the heart of Herts
Plans to improve the A41 in north-west London and Hertfordshire go back a very long way, and most of them involved simply replacing it with a whole new road. In 1936, with the Watford By-Pass still brand new, Sir Charles Bressey recommended a new route linking the A41 at Watford to Central London, part of his ambitious Highway Plan. It would start at Marylebone, pass through Harrow and Pinner, skirt the western edge of Watford and strike out towards Tring.
Building a new main road through the suburbs wasn't feasible, so the proposal was soon pared down. Under the new name "Aylesbury Radial", it became a plan for a new road from Abercrombie's "D" Ring Road at Pinner, through Oxhey, round the west of Watford to the North Orbital Road at Hunton Bridge, continuing north along the A41 as a series of bypasses.
The "D" Ring Road, of course, became Ringway 3. In 1967, when Brandt and O'Dell produced their report into Ringway 3's north-western section, recommending a new route around the north and west of Ruislip, they also told the Ministry of Transport that their modelling showed minimal demand for the Aylesbury Radial south of Watford. The Ministry evidently regarded that as one less thing to worry about, and immediately dropped the route from its roads programme, though its alignment continued to be protected, and even now a mostly vacant corridor can be traced from Pinner to Hunton Bridge.
North of Hunton Bridge, though, the existing A41 made slow progress through King's Langley, Apsley, Bourne End, Berkhamsted, Tring and Aston Clinton. The need to bypass all of those towns was still there. Now, for the motorway age, the Ministry's engineers took the 1950s sketches for a series of bypasses, joined them up, and created a new road - the A41(M) Watford to Tring Motorway.
The A41(M) was a regional motorway, serving Hertfordshire, not a long distance route, but it wasn't without ambition: planners envisaged a northern extension bypassing Aston Clinton, taking the motorway beyond Aylesbury, and references can also be found to a southern extension from Hunton Bridge to the M1 at junction 5.
For now, though, it would run from Hunton Bridge to a point west of Tring, and the Ministry wanted it built pronto.
Yes and no
An alignment for the motorway was selected in 1968 and designs were drawn up in the following two years. Planners settled on three lanes from Hunton Bridge to Hemel Hempstead, then two lanes to Tring, but there would be space for a third lane to be added as far as Berkhamsted.
Most of the route was unobjectionable, but the Tring Bypass included one striking choice, which was to pass through Tring Park, severing Tring Park Mansion from its extensive landscaped grounds. In 1968, the Royal Fine Art Commission inspected this brutal alignment, and approved it, remarking that it meant "the formal avenue and the clumps of trees could be preserved to the greatest possible effect". The bypass was built. Today the formal avenue of fine and ancient oak trees ends at the spiral ramp of a concrete footbridge, with no view of the mansion.
Work started on the Tring Bypass in 1971, and the Ministry hoped to publish orders for the remaining sections of A41(M), with a view to starting work very shortly. But a sudden halt was called in May 1971 when the Roskill Commission selected its preferred site for the Third London Airport - the village of Cublington, seven miles from the end of the A41(M). The Government then had to decide whether to go ahead with it.
Until a decision was made, announcing the A41(M) to the public was bound to look like the Government was building a motorway to Cublington, and the press would assume that was the chosen site, even though the two projects were entirely unrelated. The A41(M) had to wait.
Cublington Airport was eventually rejected in favour of Maplin Sands, which meant the A41(M) could finally go public. An inquiry was held in late 1972. With the Tring Bypass opening in 1973, it was hoped the Berkhamsted Bypass would follow soon afterwards, and the whole route would be done by the end of the decade. It was not to be.
Tring of the hill
1973 was the year of the Layfield Report into the Greater London Development Plan, and the culmination of political changes that led to the cancellation of most of the Ringway network.
Layfield had no views on the A41(M) - it was entirely outside London and therefore of no interest. But he did recommend joining the Ringway 4 Western Section at Hunton Bridge to the Ringway 3 Northern Section at South Mimms, bodging together parts of different roads to make one orbital motorway, the modern M25. Highways staff were needed to quickly design this new road and guide it through the consultation process, and money was needed to build it as a matter of urgency.
Something else had to move aside. So, again, the A41(M) had to wait. It was dropped from the Trunk Road Preparation Pool and its resources were ploughed into the new M25 project.
It was still needed, of course, but it now missed the motorway mania of the sixties and early seventies. By 1976 it was being pursued as an all-purpose trunk road, the A41, before falling further down the list of priorities. The A41(M) Tring Bypass was beginning to look like a strange anomaly, a fragment of motorway where no motorway would ever go.
The project returned again in the early eighties as a very parsimonious series of local bypasses, a dual carriageway past Kings Langley but only a single carriageway with roundabouts north of there, and as if to underline the fact that the idea of a motorway to Aylesbury was now considered borderline absurd, the A41(M) Tring Bypass was downgraded. The blue signs came down, and in 1987 it became part of the A41.
The motorway never returned, but in the following years there was a change of heart. New design work produced the modern A41, a dual carriageway largely built on the motorway alignment between Hunton Bridge and Tring. It opened in 1993, a nineties cover version of an obscure flop from the sixties.
- Route map contains OS data © Crown copyright and database rights (2017) used under the terms of the Open Government Licence.
- Plan of proposed Two Waters Interchange is extracted from CP 111.6/8.
- Photograph of A41 at Bourne End is taken from an original by Tom Presland and used under this Creative Commons licence.
- Map of Bressey's route is from the Highway Development Survey (1937), now out of copyright, and hosted by SABRE Maps.
- Plan of proposed Kingshill Interchange is extracted from CNT/HH/3/5/RD33(a).
- Photograph of Hastoe Lane underpass under construction appears courtesy of Tring Local History and is used with permission.
- Watford Bypass built in 1920s as Arterial Road: MT 39/511.
- Planning documents suggest improvement to Berrygrove Interchange: MT 120/316/2 shows possible upgrades designed after A41(M) had been dropped, but implies that they are derived from A41(M)-era proposals.
- Bressey plan for new radial via Wembley: Highway Development Survey: General Report (1937), Sir Charles Bressey and Sir Edwin Lutyens, available at MT 39/360.
- Aylesbury Radial dropped in 1967: MT 106/290.
- A41(M) northern extension to Aylesbury; line through Tring Park; approval from Fine Art Commission; plans delayed by Roskill Commission: MT 127/21.
- A41(M) dropped from preparation pool in favour of M25: MT 120/316/1.
- Hunton Bridge as first stage of three-level junction; line of A41(M); junctions and cross-section; A41(M) planning timescales and opening dates; project pursued as all-purpose in 1976: CP111.6/8.
- Proposed as single carriageway in 1980s: CNT/HH/3/5/RD33(c).