Black Balcony

In response to a Daily Mail piece today showing picture of dude ranch Wyoming in the nineteen fifties McFlyo007 asks “where are all the African-Americans?” and Stone Pillow replies “Using their own bathrooms, drinking out of their own water fountains and staying in their own motels when they weren’t going to their own schools or watching a movie from the “Black Balcony.”

Question:  Who knows what a Black Balcony was?