In 1943 art patrons Solomon R. Guggenheim and his wife, Irene Rothschild, commissioned architect Frank Lloyd Wright to design a permanent home for their collection of modern art, which today numbers more than 6,000 works. Wright considered the building his crowning achievement; few public spaces in New York rival the drama of the main gallery, encircled by the famous spiral ramp, more than a quarter-mile long. Collections range from Impressionist, post-Impressionist and early modern masterpieces to Minimalist, environmental and conceptual art. The Guggenheim also commissions works of contemporary art.