Solomon R. Guggenheim commissioned Wright to design his museum in 1943, but 13 years passed before ground was broken. The design and construction required more than 700 drawings and forced Wright to wage battles with city officials over building codes. Wright called the gradually opening, cast-concrete form a ziggurat. The design is purely sculptural, free of surface embellishments. Inside the main gallery, a quarter-mile-long, cantilevered ramp curves continuously as it rises 75 feet to the roof. A 12-sided domed skylight covers the building. Artworks are displayed on the ground floor and in the 74 circular bays that line the walls of the ramp. A lower-level auditorium accommodates 300 people. The museum opened shortly after Wright’s death in 1959.