The photographs were taken by a Mr. Barrie Wray who was sitting with his partner when they, and the snake, were disturbed by a dog out walking with a group from Walkitcornwall, who offer guided walking trips around the Lizard and other areas of Cornwall.
The photo was taken at the most southerly tip of Cornwall, Lizard point, shown below. Ironically, the rock its next to is a piece of Serpentine, a soft multi-coloured rock only found in a few locations in Britain. A strip about ten miles by two miles of Serpentine cuts across the far south of the Lizard peninsula. Its name probably comes from the snakeskin appearance of the rock. You can buy souvenirs made from Serpentine from many of the workshops and gift shops in Lizard village.