1.4 million square feet / 130,000 square meters
The Nihonbashi Mitsui Tower adds new office space, a museum, and a luxury hotel to a historic district of Tokyo. By carefully linking the 41-story tower to the landmark Mitsui Main Building and making the 1929 Beaux-Arts landmark central to the design of the new tower, the project advanced the use of historic preservation as an approach to urban redevelopment. The 41-story mixed-use tower contains the corporate headquarters of the Mitsui Fudosan Group and a Mandarin Oriental Hotel. Four basement levels include shops, parking, and subway access.
The base is formed by a rhythmic sequence of granite columns that continues the order of the marble-clad Mitsui Main Building. The design extends the cornice and entablature lines of the historic building into the tower’s base. The upper stories are set back in deference to the historic streetscape. As the tower reaches toward the sky in a series of steps, its forms become lighter and more transparent.
Each distinct form in the tower’s skyward progression reflects its use. The base and the adjacent atrium, open and filled with light, hold mostly public functions: a lobby for the offices, shops, restaurants, and an entrance to a new museum. Moving upward, the next form contains the corporate headquarters. This element’s strong, vertical organization and use of stone conveys the company’s solidity and permanence. At the top of the tower is the thinnest, most delicate and transparent form. These ten floors are the 180-room Mandarin Oriental Hotel, offering views of the Imperial Palace gardens from the guestrooms and suites.
In the new atrium, a rear elevation of the bank building — an unadorned party wall — is visible through a translucent glass wall. An image of a monumental Corinthian column was screened onto the glass, reproducing a key element of the three principal façades of the historic building. The project included interior renovations to the Mitsui Main Building, designed by the New York firm of Trowbridge and Livingston and home to Mitsui companies since its opening. On the first floor, a bank hall and atrium were preserved. The fourth floor became a banquet space for the hotel and the top floor contains a museum displaying the Mitsui collection of art and antiques.