The New York gallery that first exhibited Georgia O'Keeffe's 1915 abstractions was 291.
The gallery, formally called Little Galleries of the Photo-Secession and commonly known as 291, was founded and run by photographer Alfred Stieglitz. In 1916, he displayed O'Keeffe's abstract drawings there after receiving them from a friend who had seen her work.
The exhibition introduced O'Keeffe to Stieglitz and to a wider New York audience. The gallery had already shown European modernists and helped bring experimental photography and modern art to American viewers.
291 is sometimes confused with Stieglitz's later galleries, including the Intimate Gallery and An American Place. Those were separate venues opened after the original gallery closed.