Enhancing a prominent site

Situated at the edge of the Imperial Palace in a bustling urban center, the design for Otemachi One balances its neighborhood’s historic fabric and commercial identity. The project comprises two towers featuring offices, retail, an event hall, a Four Seasons Hotel, and new public space, each building responding directly to its surroundings.

The shorter tower—a 160-meter-tall building and the headquarters for Mitsui & Co., one of Japan’s largest trading companies—faces the palace, with its scale and materials attuned to the neighboring structures. Its detailing, inspired by traditional Japanese joinery and woodworking techniques, reinterprets this craftsmanship in masonry and glass to harmonize with the walls surrounding the palace. Conversely, the taller tower, which rises 200 meters, embodies the aesthetics of contemporary Japan with a facade of glass and steel. Its 40 stories house additional office space as well as the Four Seasons Hotel at the top.

A sustainable and resilient development

Both towers are designed with cavity walls and ventilated mullions that bring in fresh air. The buildings include a range of additional sustainable features that reduce energy use, from efficient lighting to automatic blinds. The project also presented the opportunity to improve disaster preparedness in the Otemachi district—using the most effective seismic damping structures available, the buildings are constructed to the highest standard of safety and security in Japan.

Introducing new public space

Otemachi One creates an amenity for the community. At the ground level, just across from the Imperial Palace East Gardens, a new 6,000-square-meter plaza is the largest outdoor green space in the area. The public park, called Otemachi One Gardens, features a reflecting pool and native plants, with space to accommodate outdoor programming. The design also preserves the site of Masakado’s Shrine, seamlessly integrating the historical monument within the new park.

In addition to the gardens, the lower level of Otemachi One features a variety of retail and restaurants, a direct connection to the Tokyo Metro, and health and wellness services for tenants. On the third floor of the Mitsui & Co. building, the event hall, Otemachi Mitsui Hall, offers more than 2,000 square meters of space for performances throughout the year.