The Revealer Game... Clue Number Two

After a brief summer hiatus, The Revealer returns to BackStory this Thursday!  So, you know what that means... the return of The Revealer game.  Longtime fans of the show already know the drill:  in the week leading up to the debut of The Revealer segment, we will post new photographs daily that offer visual clues to the subject of the episode.

Here's the second clue:  Are you familiar with the real estate marketing phrase, "location, location, location"?  It seems the ancient people who created these iconic structures had that phrase on their minds.

Think you know the focus of this week's episode of The Revealer?  Post your response in the comments section below.