It’s National Skyscraper Day — a holiday honoring the birthday of famed architect and Chicagoan Louis Sullivan! Since Chicago is the birthplace of the skyscraper, it seems like a perfect day to round up some fun facts about the city’s tallest buildings:
Willis Sears Tower: 1,451 feet
The city's largest tower once faced lawsuits seeking to stop its construction because of the building’s interference with local TV broadcasts. The lawsuits were ultimately unsuccessful. Once construction finished in 1973, the Sears-turned-Willis Tower held the record for world’s tallest building for nearly 25 years. (It’s now No. 25.)
Trump International Hotel and Tower: 1,388 feet
The building, constructed in 2009, is the tallest concrete skyscraper in the country. It was originally planned to be even taller, but the design was scaled back after 9/11. Last year, a judge ruled Trump Tower was a “public nuisance” for environmental violations. More recently, the tower was the backdrop for Gov. JB Pritzker’s message to the president: “Do not come to Chicago.”
The St. Regis Chicago, curvy and blue. (Beata Zawrzel/NurPhoto via Getty Images)
St. Regis Chicago: 1,191 feet
Designed by Jeanne Gang, this 101-floor building is the world’s tallest structure designed by a woman. Completed in 2020, it’s one of the city’s newer skyscrapers. Its sleek look quickly garnered multiple architecture awards.
Aon Center: 1,136 feet
Debuting in 1973 as the Standard Oil Building and nicknamed “Big Stan,” the tower was also called the Amoco Building — it finally became Aon in 1998. Also in the ‘90s, the building's white Carrara marble was replaced with more durable (and uglier) granite.
875 North Michigan Avenue The John Hancock Center: 1,127 feet
This tower’s famous Xs serve both aesthetic and functional purposes — they act as structural support for the building and were an innovation during construction in the 1960s. Now, the 95th-floor former Signature Room is becoming an observation deck. See you there in 2026!
Want more Chicago architecture knowledge? Check out our guides to architectural terms and the city’s building styles 🏙️
