This architectural complex symbolizes the continuity of modern and contemporary Japanese architecture, featuring the Central Building—designed in 1959 by Kenji Imai, a leading postwar Japanese architect—and the Main Building, designed by contemporary architect Manabu Chiba, who oversaw the preservation, restoration, and expansion of the Central Building.The Central Administration Building received the Architectural Institute of Japan Award and is registered as a National Tangible Cultural Property.It features a pioneering modernist design combined with rich ornamentation. Kenji Imai is also known for introducing Antoni Gaudí to Japan; influenced by Gaudí, he adorned the ceiling of the rooftop penthouse, the east and west walls, and the skylights on the first floor with mosaic artwork.