Tokyo Metropolitan Government Building
Dominating the western Shinjuku skyline, this grandiose, Kenzo Tange–designed complex seems to serve as a reminder that Tokyo's annual budget is bigger than that of some countries. Several other area skyscrapers have free observation floors, but those—on the 45th floors of both towers (663 feet above ground)—at city hall are the best. On a clear day, you can see all the way to Mt. Fuji, as well as to the Boso Peninsula in Chiba Prefecture. The Metropolitan Government website, incidentally, is an excellent source of information on sightseeing and current events in Tokyo.