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At classification, the A6 was made Britain's second longest road and therefore England's longest. Its start was at Barnet at London and then moved to Bignell's Corner with the opening of the Barnet Bypass. In 1986, the M25 opened and the road was shortened by 17 miles. That made the A38 and A30 roads longer and relegated the A6 down to fourth place.
It's a good job the A6 hasn't been renumbered further north than Luton, as the A6 number has gone down in UK legal history because of an incident, known as the "A6 murder" in August 1961. Michael Gregsten and Valerie Storie, employees of the Road Research Laboratory, were forced to drive 60 miles to Deadman's Hill layby from Maidenhead. Gregsten was fatally shot, and Storie was raped and left for dead. James Hanratty was executed for the crime, despite protestations that he was innocent. The case was recently re-opened, but a guilty verdict was still returned.
|1989||Market Harborough Bypass|
|1993||Rushden and Higham Ferrers Bypass|
|1996||Rothwell and Desborough Bypass|
|1993||Great Glen Bypass|
|2004||South of Leicester- A14|
|2001||South of Kettering- A45|
The Barnet Bypass opened in 1926 (see A1 entry for details), and this was renumbered to the A1 around 1954. This necessitated the renumbering of the A6 between Barnet and South Mimms (where it crossed the new A1), as this was now in the 1-zone — the stretch was given the number A1081 (reused from Woodford Avenue, which became part of the A406 and is now the A1400).
Let's start our journey from Barnet for historical/sentimental reasons. This was the point where Thomas Telford's Holyhead road of 1810 diverged from the Great North Road, and we shall follow it as far as St Albans. Once out of Barnet, we notice that we have really left London behind, and we are surrounded by fields. To the east is Wrotham Park, recently used as the setting for the film Gosford Park. However, this rural setting is short-lived as we face the M25 at South Mimms. For a few years, the M25 was continuous from Thurrock to here (it resumed to the west of Watford) and dumped all its traffic on the massive A1/A6 roundabout. The South Mimms services were built here too, on the original alignment of the A6 St. Albans Road, which now carries local traffic to and from the junction.The A6 originally went through South Mimms, however a dual carriageway bypass was built around 1970, and then the section between here and London Colney was upgraded to the M25 in 1986.
We turn off the M25 at J22 to follow the A6's route—now the A1081: the last time I was that way (a year ago perhaps), the yellow signs were still there saying "A1081 (was A6)". This part is still dual carriageway here, as it forms part of the London Colney bypass, opened in 1961. We meet the A414 which provides an invaluable alternative to the M25 in these parts, and venture into St. Albans. At the "Peahen" Crossroads in the city centre, Telford's road goes straight on, instead we cannon off the A5183 (former A5) which now takes over Telford's Baton. (This junction is the only place, apart from beginnings and ends of roads, where single digit roads met).
We continue north out of the city, still as the A1081, through the town of Harpenden, and before too long reach M1 J10a. The A6 continued straight on, now unsignposted, into central Luton (for a long time this route was still signed as the A6, with the A1081 going eastwards and meeting the A505. I don't think it was officially still the A6 though)
Until the coming of the St Alkmund's Way section of Derby's ring road- in 1972- the A6 (and indeed the zone six boundary) ran through the centre of Derby. It entered the city centre from the South via London Road (now the A5194), then met the A514 at The Spot and the A38 at Babington Lane. The A6 then ran along St Peter's Street where it met the obscure B5021 and then onto Cornmarket and Iron Gate. At the junction between Iron Gate and Sadler Gate, an old sign can be seen which reads 'A6'. From Iron Gate the road mostly followed its old course towards the peak district.
The modern A6 multiplexes with the A601 around the ring road, hence the disappearance of the A6 through the city centre.