The Denver Art Museum is one of the largest art museums between Chicago and the West Coast, with a collection of more than 70,000 works of art divided between 10 permanent collections including African, American Indian, Asian, European and American, modern and contemporary, pre-Columbian, photography, Spanish Colonial, textile, and western American art. In 1971 the museum opened the 24-sided, two-towered North Building by Ponti in collaboration with James Sudler Associates of Denver. On October 7, 2006, the Denver Art Museum nearly doubled in size when they opened the Frederic C. Hamilton Building which includes new galleries for its permanent collection, three temporary exhibition spaces, art storage, and public amenities. The entire museum complex totals more than 350,000 square feet. The 146,000-square-foot Frederic C. Hamilton Building, a joint venture of Daniel Libeskind and Denver-based Davis Partnership Architects in 2000, is situated directly south of the North Building. Libeskind's design, referential to the original Ponti building, recalls not only the mountain peaks that provide a powerful backdrop for the city, but the intricate and geometric rock crystals found in the foothills of the Rockies.