An exceptionally rare, original vintage 1977 New York City art exhibition poster titled "Art in Public Spaces". The poster was published by the Organization of Independent Artists (OIA) to advertise their landmark multi-site downtown exhibition running from September 26 to November 25, 1977.The poster features a fascinating dual-panel, highly detailed illustrative map design of Lower Manhattan drawn by noted artist Bill Barrell. The layout tracks historical exhibition sites, including the U.S. Custom House, Foley Square, Federal Hall, and Castle Clinton.In the lower right-hand corner, the poster features a large, beautifully preserved original inscription and signature from the artist, boldly written in vibrant blue ink: "For Christopher, Bill Barrell, 4th of July, 1986. Dimensions: Approximately 24 inches high by 31.5 inches wide (standard large vintage exhibition format). Good to Very Good vintage condition. The front graphic remains incredibly clean with crisp text, deep black and yellow inks, and an unblemished artist signature. Light, age-appropriate handling crinkles are present along margins. The reverse side reveals a distinct, horizontal two-tone band of light amber toning along the bottom third edge—consistent with long-term placement inside a vintage backing frame.