Aon Center (Chicago)

The Standard Oil Building in Chicago was completed in 1972. At 1,136 feet (346.3 m) tall, it is second only to the Sears Tower in height in Chicago. When the building was originally built, it was the world's tallest marble clad building. Eventually, the Carrara marble that sheathed the building began to buckle and roll off the building. From 1990 to 1992, the coating was replaced with granite. The building employs a tubular steel-framed structural system with V-shaped perimeter columns to resist earthquakes, reduce sway, minimize column bending, and maximize column-free space.

"Big Stan" as the building was often called, it was also known officially as the Amoco Building. After the building was sold, it became known officially as the Aon Building.