Nishi-Shinjuku
Nishi-Shinjuku (literally West-Shinjuku) is a skyscraper business district west of the Shinjuku train station, in Tokyo.
skyscraper
Tokyo from above: 12 skyscraper observatories
Tokyo has many skyscraper observatories open to the public. On a clear day, it is even possible to see Mount Fuji and a good part of Kanto. Here is a list of the ones I have visited so far. I have also made a map to show locations.