Roppongi Hills Mori Tower is a 54-story mixed-use skyscraper located in Roppongi, Minato, Tokyo. Completed in 2003 and named for builder Minoru Mori, it is the centerpiece of the Roppongi Hills urban development. It is currently the sixth-tallest building in Tokyo at 238 meters (781 ft). The tower has a floor space area of 379,408m squared (4,083,910 sq ft), making it one of the largest buildings in the world by this measure.
The Mori Tower building is primarily used for office space, but it also includes retail stores, restaurants and other tourist attractions. The Mori Art Museum is located on the 53rd floor and visitors can view the city from observation decks on the 52nd and 54th floors. https://en.wikipedia.org/wiki/Roppongi_Hills_Mori_Tower