Now known as the Aon Center, this was originally constructed in 1974 as the Standard Oil Building (later, the Amoco Building).
It is Chicago's third tallest building (behind the Willis and Trump Towers) at 1,136 feet (85 stories).
The building at left, with pyramidal cap is Two Prudential Plaza. From this angle
(taken on a snowy Christmas Eve day, from the Maggie Daley Skate Ribbon),
it looks significantly shorter, but it is Chicago's sixth tallest building at 995 feet (64 stories).