The question was asked, what was the largest paved area in the world?

Question

The answer should have been the Hoover damn.
Combined with its top thickness of 45 feet, there is enough concrete (4.5 million cubic yards) in Hoover Dam to build a two-lane highway from Seattle Washington to Miami Florida. Or imagine a four-foot wide sidewalk around Earth at its equator. check it out, it's very interesting.
http://www.arizona-leisure.com/hoover-dam.html

Now here is another for you? What structure was built so massive that it can circle around the world at the equator five times? That should be easy enough if you look it up.
First one to get it right wins!

Answer 1

The great wall of china.

Answer 2

Sears Tower