Innes and Augustus John painted together at Nant-Ddu in autumn 1911 and summer 1912. John wrote that Innes 'was never happier than when painting in this district'. Arenig is the name of the mountain to the north-west of Lake Bala, the shore of which can be seen in the foreground, viewed from Nant-Ddu. This is the largest and latest of all Innes's known paintings of Arenig, and it may have been completed in London rather than on site in North Wales. It shows the influence of pictures by Matisse and Le Douanier Rousseau, which Innes may have seen in Paris.