7) The Citadel
As the housing for the Citadel Council in the Mass Effect series, The Citadel certainly has some almighty significance in its universe. Superbly located at the junction of a few Mass Relays and with a comfortably manufactured atmosphere, it is truly the home of tomorrow!
It also happens to be known as the political and cultural heart of citadel space, making it an attractive destination for any socialites out there. You could spend the morning studying the collective histories of various colonies, before taking in some high culture in some of the more arty districts after noon.
Think of it like Paris….in space.