Among the most dramatic and well-known images of O'Keeffe's later years are her cloudscapes of the 1960s and '70s. Traveling around the world, she was exhilarated by the views seen from an airplane window. She described the changing patterns and colors as "breathtaking" and was moved to interpret these sights and feelings in paint. At first she painted contemplative pictures that showed the sky covered with a blanket of solid white clouds; later, a series of lively canvases filled with puffy white clouds and blue sky that stretch to infinity. O'Keeffe's Sky Above Clouds IV of 1965 was the most ambitious work in the series, and realized her long-time ambition to create a huge mural-size painting.