The Shinjuku Mitsui Building is a 224 meter skyscraper in Shinjuku, Tokyo. It is the eighth tallest building in Tokyo, and was the tallest building in Tokyo and Japan, from September 1974 until March 1978, when Sunshine 60 was completed. It was built in the style of American buildings that were being built at around that time. The thing that made it stand out was the black channels running down its east and west sides. At the base of the skyscraper, there is a sunken garden and a surprisingly large plaza. In addition to the sunken garden, there is also a roof-top garden.