As cars and lorries snail interminably along the A30 in Cornwall – the county’s notorious trunk road – the words of the furious driver in John Betjeman’s poem, Meditation On The A30, seem befitting: “I can’t go on crawling like this!”

Such frustrations are especially acute in summertime when tourists compete with hauliers, tractors and local residents for space on the asphalt, many of them en route to the coastal hotspots of Perranporth and St Ives. But those days could soon be gone.

A £330m roadworks scheme is nearing completion, with National Highways creating an 8.7-mile stretch of dual carriageway between Carland Cross and Chiverton, parallel to the existing A30, bringing the promise of prosperity for the local economy, as well as fears for the environment at a time of global heating.