Two Visitors to Avebury (B&W)

I visited Avebury in August after the heatwave had ended. It was a bright day, but not unbearably hot. As I rounded the Devil's Chair en route to the beech clump by the Marlborough Road junction, I chanced upon this couple and impulsively asked if I could take their picture.
I'm still getting used to using the 35mm fixed focal length, and my first shot was too much stone, too little people. The second was better, but not much. This was my third and final photograph; the couple remained good humoured throughout and I hurried off lest my intrusion became boring.
I can never assess at the time I make a picture if it is going to be good. So many technical things can be wrong; I sometimes find features which I did not notice in the viewfinder; and with people, their eyes can be closed or I accidentally catch a funny expression. I was glad, therefore, that I cheekily persisted for this third shot. I prefer it in black and white.