The first modern artifact built to last (was Larger habitats can orbit lower)

--- In spacesettlers@yahoogroups.com, Al Globus wrote:
> given no inputs I would not like to see a habitat with an orbital lifetime of under a century or two.

That reminds me of Life After People. Can you think of any mega-structure built after 1800 that would survive even 50 years without inputs? Here's a 2-minute video of many of the greatest megastructures of the last two centuries collapsing almost as soon as humans were to vanish:
http://www.youtube.com/watch?v=X5rw_K6HsPo

"the Empire State Building, the Sears Tower, the Space Needle, the Eiffel Tower, the Burj Khalifa, the Golden Gate Bridge, the Gateway Arch, Taipei 101, the USS Constitution, the Hoover Dam and the Sydney Harbour Bridge, Grant's Tomb, and Air Force One"

Such a habitat would be unique in that respect (of centuries-long survivability) among large modern human artifacts, don't you think? When you say "orbital lifetime" do you mean in one piece, or many pieces? What would prevent orbital debris and tidal forces from tearing it apart?