I live in Swindon (Wiltshire) and since the beginning of the year I have been walking round the town looking for 'stray' sarsens - at first I thought they were just around the Coate Water area which is the part of Swindon closest to the Marlborough Downs. However, once I started looking they seem to be all over the town - yesterday I spotted the largest ones yet on the corner of a green open space in an area called Rodbourne Cheney. I believe they have been imported from the Marlborough Downs.

There is also evidence that many of these stones (known locally as 'grey wethers') have been buried by local farmers.

PS: I'm a bit of a fan of John Betjeman so will make a point of visiting the park at some point in the future.