MoMA - Picasso.

Les Demoiselies d'Avignon, 1907

"The result of months of preparation and revisions, the painting revolutionized the art world when first seen in Picasso's studio. Its monumental size underscored the shocking incoherence resulting from the outright sabotage of conventional representation. Picasso drew on sources as diverse as Iberian sculpture, African tribal masks, and El Greco's painting to make this startling composition. In the preparatory studies, the figure at the left was a medical student entering a brothel. Picasso, wanting to anecdotal detail to interfere with the sheer impact of the work, decided to eliminate it in the final painting. The only remaining allusion to the brothel lies in the title: Avignon was a street in Barcelona famed for its brothel."

This was a gasper for me. I'm pretty sure I've seen it before, but then it shows up surprisingly, and wakes me up inside.