This sunset scene is probably one of Turner’s colour ‘Beginnings’. This was his own name for watercolours in which he used colour washes on saturated paper to develop a composition, rather than first mapping it out in pencil. The subject is most likely the town of Sion, capital of the Canton Valais in Switzerland, seen from the south-east. As a rule, Turner sketched in pencil and only later applied colour to his drawings, but this watercolour may have been done on the spot. It is Turner’s response to the colours and sensations of being in the mountains at dusk.