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East Building Architectural Tour

Interior, Atrium

Bridges and mezzanines create a vertical orientation throughout the East Building. When visitors leave one exhibition, they return to the atrium before entering another one. The triangular layout of the floor plan generates a sense of exploration: one must choose to turn left or right, go up or down.
The atrium's indoor garden, which is larger than one-third of an acre, is roofed by a "space-frame" of glass pyramids. A screen of aluminum rods reduces the sunlight so that visitors' eyes adjust to the galleries, where dimmer light levels protect the works of art from fading. This space-frame roof also animates the interior by casting a changing pattern of shadows over the walls and the mobile Untitled, commissioned for this space from Alexander Calder.
Audio: I. M. Pei and Earl A. Powell III