U.S. Steel Tower in Pittsburgh, Pennsylvania. The building is 64 stories high with an acre of office space on each floor and is constructed from Cor-Ten steel. Photography by Derek Jensen.

U.S. Steel Tower in Pittsburgh, Pennsylvania. The building is 64 stories high with an acre of office space on each floor and is constructed from Cor-Ten steel. Photography by Derek Jensen.

U.S. Steel Tower in Pittsburgh, Pennsylvania. The building is 64 stories high with an acre of office space on each floor and is constructed from Cor-Ten steel.

Photography by Derek Jensen.