"The blue hour (from French l'heure bleue) is the period of twilight in the morning or evening, during the civil and nautical stages, when the Sun is at a significant depth below the horizon and residual, indirect sunlight takes on a predominantly blue shade." ~Wiki
Taken just after sunset of Governor Albert D. Rosellini Bridge, aka the Evergreen Point Bridge, across Lake Washington viewed west, to Seattle. It is the world's longest floating bridge. 