You usually see the Wrigley building in night photos, bathed in the bright white lights that illuminate it. It's actually two buildings, joined by that little walkway you see about halfway up. No one ever shoots it from the side . . . except me :-) It really is very beautiful - it was a grey day here today, and so it's white terra cotta seems to reflect the sky. It always looks brighter when the sun is shining.
The buildings are uniquely shaped. Here's a history from the Wrigley website if you are interested.