This is the weir and ruined mill at Coatigrac'h Lock - lock no.235 on the Nantes-Brestes Canal near Chateaulin in Brittany. The canal was first conceived in the 16th century, but it wasn't until Brest was blockaded by the English fleet that Napoleon I of France decided to build this canal to assure a safe inland link between the two largest military ports on the French Atlantic front. Building started in 1811, and Napoleon III of France presided over the canal's opening in 1858. The canal is 385km long and there are 238 locks.
Today, this is a bucolic scene but in the past, the ruined building at centre right housed a hydroelectric power station.
As usual, this image is SOOC and is part of my ongoing OCOLOY project - you can read more about it in my profile.