Kagawa Prefectural Government Office, East Building (香川県庁舎東館)

Governor Masanori Kaneko commissioned Kenzō Tange to design the new prefectural government building through an introduction by the painter Gen'ichirō Inokuma, a native of Kagawa. He set two conditions: a building worthy of a prefecture in the age of democracy and worthy of the main building of a tourist prefecture. Tange's laboratory (Kenzō Tange, Takashi Asada, Taneo Oki and Kōji Kamiya) worked on the project from 1954 to 1957, garden included, with Yoshikatsu Tsuboi responsible for the structure. A drawing dated 10 June 1955 already shows the core rising at the centre of the tower like a spine.

Construction, carried out by Obayashi, ran from December 1955 to May 1958, and the building was completed on 26 May 1958 as the prefecture's main building. The present main building, finished in 2000, stands behind it, and the older one is now called the East Building.

The building won the BCS Prize in its first edition, in 1960, entered the list of the Hundred Public Buildings in 1998, and in 1999 the DOCOMOMO Japan selection of twenty modernist buildings, which singled out the spaces set aside for local people, the expression of tradition, the collaboration with artists and the core with its central seismic wall. Seismic reinforcement work was completed on 20 December 2019. On 9 February 2022 the building was designated an Important Cultural Property under the name “former main building and East Building”, which covers its tower and its low wing.

The building is of reinforced concrete and has two parts: an eight-storey tower topped by a three-storey rooftop structure, and a low three-storey wing. It is 43 m high. Here Tange achieved what he was seeking: an expression of traditional Japanese architecture in reinforced concrete, through posts, beams and eaves of a light design.

The posts and beams recall timber construction, and the verandas have a balustrade: two features of traditional architecture rendered in a modern material. For Kenneth Frampton, the concrete frame cast in place in boarded formwork has a proportion and rhythm that recall Japanese timber framing. The formwork was of Japanese cedar boards, whose grain marks the concrete of the posts and beams, and the balcony around the building keeps out direct sunlight.

At ground level the piloti, about seven metres high, makes a natural approach from the street; a round stone lantern there was designed by Tange. The piloti, the ground-floor lobby and the south garden, with its small hill, run into a single space for local people. The lobby is fully glazed and holds Gen'ichirō Inokuma's mural "Wakeiseijaku": the artist read the ideal of postwar democracy in the spirit of the tea ceremony. The Tange laboratory designed the wooden and ceramic chairs, the wooden shelves and the stone tables; the reception desk is of Aji granite. Isamu Kenmochi designed the governor's desk, as well as the lectern and seats of the prefectural office hall, whose red entrance door is finished in gotō lacquer, one of Kagawa's lacquer crafts.

At the centre of the tower, a concrete seismic wall forms the spine of the building; stairs, lifts and toilets are housed in this core, and the offices are partitioned freely along the small beams. These arrangements, together with a ground floor open to local people, made the building a model for the government buildings put up across the country afterwards. Construction used a technique that was then unusual: the joints of the reinforcing bars were gas-pressure welded.

The Tange laboratory also designed the south garden. It breaks with the idea, attached to the Japanese garden, of a wish for its owner's longevity: the Aji granite stones set in the pond are a symbol of good harvest, for a prosperous life for local people. At the governor's suggestion the roof terrace was opened to the public as well, and people could have a coffee or a beer there while looking out over the Seto Inland Sea.

Offices of the prefectural administration are housed here. The piloti, designed from the start as a square for local people, hosts events.

The piloti, the ground-floor lobby and the south garden can be visited. The interior is open Monday to Friday, from 8:30 am to 5:15 pm, except on public holidays and over the year-end and New Year period. The offices are off limits, and the roof terrace is not open to visitors.

The building stands in the centre of Takamatsu.