One of my favorites of his shots is this above-the-clouds one, with a few downtown buildings peeking above the clouds. There is a famous photo of the twin Towers that is similar, some girl took the photo from an airplane. This one is just a crop out of the middle of a larger photo. The building toward the right end, that seems to have 2 horns, is the PPG, or Pittsburgh Plate Glass Building, which resembles a glass castle.

Closeup:
