A666

Route

The A666, in journalistic circles referred to unflatteringly as the Devil's Highway, connects the district of Pendlebury in Salford with the A59 in the rural Ribble Valley. Its journey lasts for just under thirty miles, and the road varies from motorway-standard dual carriageway to narrow urban town street.

Section 1: Pendlebury – Bolton

We shall begin at the southern end, at the junction of the A6 and A580, which in the pre-motorway era was a simple fork junction, but now it is a complicated roundabout GSJ mixed with a one-way system for the A6. The A580 feeds directly into the 1970s A6 Broad Street – a six lane urban dual carriageway right into the heart of Manchester. The A666, however, has a rather more modest start as a 30 mph single carriageway. It is, for this section, non primary.

Drivers through this section are reminded with garish pink signs that it is an offence to drop litter "IN Salford", the current branding for the city, and it passes through typical suburban semi-detached houses whilst giving a distinct impression it was once a major road, although these days the A580/M61 takes the major strategic traffic. At one stage the road reverts to its former glories and features a four-lane single carriageway section into Swinton. The road retains its urban character until it crosses the M60 Manchester Outer Ring Road in the "Death Valley" section. This junction, J16 only permits traffic to access the clockwise carriageway, near to where the proposed M601 Irwell Valley Motorway would have branched off, further bypassing this road.

After crossing the motorway, the A666 passes Kearsley electrical substation which is in a deep valley to the north of the road itself, and enters the Metropolitan Borough of Bolton. The layout of the road once again suggests this was once a much busier road, perhaps even with four lanes – it is worth noting that many of Bolton's radial routes once sported four lanes – but remarking schemes have eradicated a vast proportion of these. There is nothing much in the realms of interest until the road passes the A667 at a signalized junction and then widens out to hit a large roundabout at the top of the hill. This marks the end of the non-primary section of the A666.

Saint Peter's Way

Ahead is the original road, but through traffic is ushered right onto a slip road, where it meets the end of the A666(M), to become the Farnworth–Kearsley Bypass. Opened in 1967, some years before the M61 it now links into, it originally only went as far as the next interchange, with the now-A575, where it rejoined the old road. It now, however, forms a motorway-standard link into the centre of Bolton, bypassing the old slog along Manchester Road. When opened, this bypass had a 70 mph speed limit, but this was reduced to 50 mph in 1999, along with the introduction of speed cameras and a prohibition on cyclists. In the late 2010s the fixed cameras were replaced with an average speed check system, and the road was resurfaced and relined in time for its 50th birthday in 2021.

After some unusual interchanges, notably with the A575, and Raikes Lane, once busy as it was the exit for Burnden Park football ground which was closed in 1997, there is a regular diamond interchange with the A579 that now sports one of Bolton's numerous CYCLOPS Junctions. The A666, known here as Saint Peter's Way because of the large church it passes on the left, gains a third lane here, and on the southbound carriageway a brand new entrance slip road opened in 2007 to enable better exit routes from the town centre. Immediately beyond this junction, the speed limit drops to 40 mph, the left hand lane peels off into Saint George's Road for the town centre, and the = expressway standard road ends at a set of traffic signals completed in November 1988. Whilst this is a vast improvement over the original terminus, at the aforementioned Saint George's Road, it still can cause considerable queues at rush hour. Proposals for an extended expressway towards Astley Bridge have never been realised, and the land originally earmarked for it is now occupied by The Valley retail park.

Section 2: Bolton – Blackburn Town Centre

From here on the road is 30 mph, and passes through a couple of large signalised junctions with Halliwell Road (the A6099), and Water's Meeting Road, which will loop back to the A666 about half a mile ahead. Now on Blackburn Road, which is a wide single-carriageway where drivers treat it as four lanes, requiring caution when moving past parked vehicles, there are numerous side turnings until the return of Water's Meeting Road where there is a very brief dual carriageway before the road sweeps past a signalised junction (installed in 2007) for the Astley Bridge supermarket. Directly beyond this the A58 ring road crosses the A666, at the Pineapple Pub. This junction was largely rebuilt in the early 1990s and rebuilt again in 2022, but remains a significant bottleneck for all approaches, as the A675 from Preston also piles in here to add to the mix of traffic. Continuing further north, the A666 starts to become narrower as it passes through Dunscar and heads towards Egerton. This part of the road was once a 40 mph limit but was reduced to 30 mph in the 1990s. From Dunscar, there is a mostly uphill climb onto the West Pennine Moors.

On the moors

Once beyond Egerton the A666 gains a 40 mph limit, and follows the line of a former turnpike across the moors. The speed limit rises again to 50 mph (although originally this was 60 mph), and passes bleak moorland scenery typical of east Lancashire. The junction with Stones Bank Road has recently been modified to try and improve the previously poor visibility, particularly as it is situated on a sweeping bend. Beyond this, there is another notorious junction with the B6391 in a dip, which has seen a disproportionate number of collisions. Following this the road soon enters Darwen, where a former 30 mph limit now applies from the site of the former Bull Hill Hospital, meaning that this section has had its speed limit halved in less than fifteen years. It was once 60 mph all the way to Cemetery Road, but was reduced to 40 mph and then again to 30. In 2014, this 30 limit was returned to 40 mph after a lengthy political process and several changes to the layout of the road markings.

Cemetery Road's beginnings are marked by a sudden transition to terraced houses and a sudden descent of 1 in 10. The speed limit is enforced by two cameras at the Swan Hotel near Whitehall Park, and the road drops further beyond Mayfield Estate and into Darwen proper at the junction of Hardman Way. This area has seen significant traffic management changes in the mid-2000s, all of which have proven to be very controversial. Darwen Circus's modifications have not eased traffic congestion, but have created a very convoluted one-way system past the former swimming baths which have since been demolished, again amidst much controversy. Anyone unfamiliar with Darwen would be stunned by the level of demolition in the town centre for projects such as city academies and new leisure centres.

As a driver, it is perhaps best to leave it all behind and continue northwards along the A666 – although it'll be at a walking pace as this section of road is very urban and not very wide, resulting in regular heavy congestion. Proposals for a bus lane along this stretch in 2008 were met with significant controversy and were mostly shelved. In 2014 a much smaller project commenced which saw new signals installed at Hollins Grove, which have been met with numerous protests owing to the original controversy.

A further continuation through terraced houses brings traffic within reach of the junction with Earcroft Way and thus the M65. Turning right here allows access to the M65 at J4 and also the village of Lower Darwen. This junction has some of the heaviest congestion and air pollution in the region of Blackburn with Darwen, owing to the sheer volume of traffic such a cramped signalised junction has to process, although a new layout completed in 2016 is designed to ease problems somewhat. Once clear of this hurdle it's a fairly straight run down a shallow hill through a set of signals with Jack Walker Way and then past the bus lane approaching Branch Road where the B6231 commences (completed in 2015). After passing the former signals with the northern end of Jack Walker Way, which were replaced with a mini roundabout in 2016, the Ewood Park football ground is passed on the right as traffic is routed on Alan Shearer Way, and then there is a signalised junction with Aqueduct Road, which forms a semi-bypass for the western side of the town. The A666 continues ahead and heads under the Blackburn–Manchester railway line, which was last seen crossing over the road on a huge viaduct over Saint Peter's Way. However, this time the bridge is restricted to vehicles under 14'9". There is soon a brief dual carriageway before traffic is thrown onto the newly formed A6078 ring road. On the left is a new road bridge, opened in June 2008, which would be the best route to follow, as the A666 now stops here. It originally ran through the town centre (along Darwen Street and Penny Street), but pedestrian zone schemes have changed this.

Section 3: Blackburn Town Centre – Langho

The A666 resumes on Lark Hill, at the other side of the ring road, and becomes Whalley New Road at a mini-roundabout. This is another former turnpike – the older road branches to the right. This is another narrow urban slog not too different from the one in Darwen, with numerous side turnings. Another low railway bridge is passed at Roe Lee, this one with a 14'9" restriction too. Before too long, the A6119 Blackburn Northern Bypass is crossed at a complex signalised junction that replaced a hideously cramped roundabout in the mid-1990s and was further rebuilt in 2018. Whalley New Road continues beyond the junction and soon leaves Blackburn with Darwen to enter the Ribble Valley. A fork junction with the B6245 to Ribchester is soon encountered and high vehicles over 13'0" must turn left here. This is due to a low bridge in Langho, which has seen numerous strikes by lorries.

Approaching Langho

The final leg of the A666 is semi-urban, with a brief 40 mph limit between Wilpshire and Langho – the first limit higher than 30 since Bull Hill. In Langho itself there are two mini-roundabouts with local roads, but nothing of particular merit in a roads context. Once beyond these roundabouts the low bridge is passed, before the road curves to the left, with the original alignment to the right. This is because of the A59 Whalley–Clitheroe Bypass which was opened in 1970. The speed limit now rises to 60 mph before the A666 itself joins an absolutely huge roundabout which was planned to have a full dual carriageway passing under it, but was never built. The options for the driver are now to turn around, and go back to Manchester, to turn left and go to Preston, or to turn right and go to Clitheroe and beyond – eventually reaching York.