The Lock of Saint-Mammès (L'ecluse de Saint-Mammès)

Throughout his career, Sisley was especially attracted by river scenes, often focusing on images of river traffic. This painting shows the confluence of the rivers Seine and Loing, southeast of Paris at the village of Saint-Mammès, where Sisley had moved in 1880.

A range of boats is depicted, from the barge that glides along at far right to the construction boat on the left, carrying scaffolding. To the left is the red lockkeeper's shed, with its blue roof, but the lock itself is barely visible in the middle ground. This painting is particularly notable for its radiant ultramarine blues and the careful study of light effects on water.