“Sunset over a Lake” exemplifies William Turner’s late painting at the threshold of abstraction. The focus is not on a precise depiction of a landscape, but on the dissolution of the visible world into light, haze, and colour. The lake, the shore, and the horizon remain merely suggested; what truly matters is the radiant atmosphere of the sunset. Turner intensifies shades of yellow, orange, and red into an almost incandescent vision, while cooler areas create depth and a sense of movement. It is precisely this free treatment of nature and light that made him a key precursor of modern landscape painting. Created in 1840, the work belongs to the late phase of the English Romantic painter and demonstrates how far Turner had already led traditional landscape art beyond its established boundaries.