Ibm Building

1200 Fifth, formerly the IBM Building, is a 20-story office building in Seattle's Metropolitan Tract. The renowned architect Minoru Yamasaki designed the building, which was begun in 1963 and completed in 1964. Its architecture is especially noteworthy: the structure rests on a base of twelve load-bearing arches that carry the weight of the bundled-tube structure above down into the underground parking garage below. The facade consists of high-strength steel tubes wrapped in white precast concrete elements, which also serve as sun shading. The crown of the tower is marked by a series of fins around the mechanical floors. Yamasaki also designed the surrounding plaza, a feature that defines his work and stems from his early exposure to public spaces in New York City.