Under the thrum of the A1: sunbeams, hoofprints and pearly ice spears

Sandy, Bedfordshire In the concrete underpass, chemicals leach and stain, yet here the sun can pierce blight with beauty

Two bridges cross the river, 300 metres and an aesthetic mile apart. A little downstream, 18th-century builders had carried the old Great North Road over the Ivel in the only way they knew, fashioning pretty arches from local stone and a humpbacked road wide enough for two carriages to pass.

Here, their 20th-century counterparts twinned it with something bigger. Committed to a four-lane, prosaically named A1, they used an all-prevailing material that could be relied on for strength, durability and ugliness.