The Stonehenge tunnel scheme and the madness of Treasury Brain

How does it make sense to spend £1.7bn on a dual carriageway through a Unesco World Heritage Site, but not to invest in Britain’s railways?

By Jonn Elledge

It may have been a temple, its stones constructed in such a way as to align with the sun at the solstices. It may have marked an ancient burial ground. Whatever its purpose, though, Stonehenge is pretty much the oldest man-made thing you’ll find anywhere in England: its stones have stood for at least 4,500 years, further in the past to the Romans than the Romans are to us, and even when they went up other elements of the site were already ancient. All this makes it one of the most important prehistoric archaeological sites on these islands; it has had Unesco world heritage status since 1986.

It also, alas, sits beside the A303, which connects Basingstoke and Honiton in Devon, and thus links London to the far west. All this is very handy if, say, you want to swing past on the way back from a wedding, take one look at the queues and the ticket prices and decide that you will, on this occasion, be happy to view the ’henge through a distant fence while eating some ice cream. But there is some argument that this intimate relationship between ancient monument and major trunk road may also have its downsides.

Which is why, for three decades now, the government has been plotting to separate the two. The latest iteration of the eight-mile A303 Stonehenge scheme would mean upgrading some single-lane stretches to dual carriageway, and a bypass for the picturesque-sounding but traffic-clogged village of Winterbourne Stoke. In the immediate vicinity of Stonehenge itself, it would mean a two-mile tunnel, 200 metres away from the stones and roughly 40m beneath the ground. This, we are told, would speed up journeys between London and the west, and make it possible to view the site again in the silence of the ancient plain rather than the buzz and smoke of passing traffic. What’s not to love?

Well, the scheme’s many opponents say: rather a lot. Salisbury Plain has been attracting human visitors for about as long as humans have been living in the area. It isn’t merely the stone circle itself whose importance has been recognised, but a wide stretch of surrounding land, taking in various other historic sites and containing evidence of ancient human settlement or auroch migration routes alike.

Only a fraction of the new road would be in the tunnel: the rest of the length would mean a new dual carriageway through the middle of a Unesco World Heritage Site. More than that, while archaeology is painstakingly slow and careful, construction work involves moving large chunks of earth as quickly as possible. Building a tunnel through won’t just mean that things are destroyed: it means we’ll never even know what we’ve lost.

Oh, and those faster journeys? Highways England reckons that the average time-saving on a 100-mile journey would be just eight minutes (4.8 seconds per mile). The historian Tom Holland, who doubles as president of the Save Stonehenge World Heritage Site campaign, has described the project as “the gravest act of desecration perpetrated by any recent British government”.

As a result, while the government and Wiltshire Council seem enthusiastic about the transport benefits of the scheme, many others are not. The Planning Inspectorate, an agency of the levelling-up and communities department, has warned it will “introduce a greater physical change to the Stonehenge landscape than has occurred in its 6,000 years as a place of widely acknowledged human significance”. Unesco has warned that the scheme could see the site lose its world heritage status.

Campaigners got the plan quashed by the High Court in 2021 and are hoping to defeat it again now. I’m not generally one to side with Nimbys; but siding with a bunch of archaeologists and the Unesco World Heritage organisation is quite another thing entirely. (In the name of balance I should note that the heritage sector is not always consistent: Unesco said it “regretted” the cancellation of an earlier version of the tunnel scheme in 2007, while Historic England seems fairly enthusiastic about the idea of doing something about those traffic jams, and in 2021 bemoaned the success of the judicial review blocking the project.)

There is, to my mind, another reason to doubt this particular project: the opportunity cost it represents, and what this tells us about Treasury priorities. The scheme will cost an estimated £1.7bn, which given the way megaproject finances go is almost certainly an underestimate; the government’s largely unscrutinised road investment strategy covering 2020-25, RIS2, is worth a grand total of £27.4bn, roughly one and a half Crossrails. And all we get out of it is slightly wider roads.

Meanwhile, the government has scrapped plans to build two more through platforms at Manchester Piccadilly, which would unlock vast amounts of capacity in the north’s rail network for a relatively modest £800m. The cost of the Midlands Rail hub, which would involve two new “chords” and a dozen other engineering interventions to allow 100 extra services a day in and around Birmingham, is estimated at £900m-£1.5bn. That doesn’t have funding either.

At the time of writing, southern Europe is about to enter what is unnervingly referred to as a “heat storm” for the second time in a week. Temperatures could breach the previous record of 48.8°C. And yet, as ever, the Treasury sees road building as investment but the railways merely as cost, and seems more enthused about spending money in the south of England to boot. Its apparent determination to ruin Salisbury Plain is not the only way in which that ghastly institution seems determined to cause millennia worth of damage.