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Reaching New Heights: A Willis Tower Timeline

Reaching New Heights: A Willis Tower Timeline featured image

You’ve probably heard of the Willis Tower (formerly known as the Sears Tower). You know that it was the tallest building in the world for a long time. And that it dominates the Chicago skyline. But do you know everything that’s gone on in this iconic building since it was first dreamt up in 1969? Check out our timeline of the major events of Willis Tower history.

1969 – Sears Roebuck, the largest commerce company in the world, decides to consolidate all their employees into one building. Planning begins, and a location on the Western edge of the Loop is chosen.

1970 – Construction begins on the Sears Tower. It was built with the innovative “bundle tube structure” strategy – the building is essentially made up of eight different tubes of varying heights.

1973 – Construction is completed. At 1,450 feet, the Sears Tower passes the Empire State Building as the tallest building in the world.

1974 – The Skydeck observatory on the 103rd floor of the tower is opened. At 1,353 feet, visitors can see stunning panoramic views that span four states.

1984 – Two television antennas were added to the tower, increasing its height to 1,707 feet.

1985 – The tower undergoes renovation, and a new atrium is built.

1992 – Sears begins to move its employees out of the building.

1994 – Sears sells the building to Boston-based firm AEW Capital Management. Over the next nine years, the Sears Tower will change hands twice before being sold to investors.

1995 – All Sears employees move out of the building. The company establishes its new headquarters in the suburb of Hoffman Estates.

1996 – The tower begins in its efforts to “go green.” By 2016, it would reduce its electricity consumption by 34%.

1998 – The Petronas Towers are built in Malaysia. By some measurements they are taller than the Sears Tower – however, this does not take the height of antennas into consideration.

2007 – The Burj Khalifa in Dubai surpasses the Sears Tower in all height categories.

2009 – London-based insurance broker Willis Groups Holding agrees to rent out a portion of the building if they can obtain naming rights. The building is subsequently named the Willis Tower.

2009 – The Skydeck receives renovations. The biggest new development is arguably the retractable glass ledges that can extend four-feet out of the building’s façade.

2015 – Blackstone Group purchases the tower for a total of 1.3 billion. Outside of New York, this is the highest price ever paid for a property in the United States.

Explore more architecture and engineering on a Chicago STEM tour!