Think you know all the facts about Chicago? All throughout the city, you’ll find fascinating pieces of history waiting to be discovered. We think it’s impossible to know everything, but you can start with these surprising Chicago facts to learn more about our very own Windy City!

Birthplace of Modern Architecture

It stood only 10 storeys tall, but Chicago’s Home Insurance building was the world’s first skyscraper. From Willis Tower to the grand Graystones along Logan Boulevard and Lawndale Avenue, Chicago isn’t afraid to make a statement. In fact, Chicago’s daring designs and groundbreaking engineering feats have influenced architecture worldwide.

Nation’s First Open-Heart Surgery

Already making history as one of the first black physicians in the city, Northwestern University graduate Daniel Hale Williams performed the nation’s first-ever open-heart surgery. As a result of the groundbreaking 1983 surgery, the patient was able to recover from a stab wound near the heart in less than two months!

World’s Only Backwards-Flowing River

In the largest public earth-moving project ever completed, in 1900 the Chicago River was engineered to flow backwards! This incredible achievement has a very practical purpose: to divert sewage away from Lake Michigan’s freshwater supply.

Start of the Atomic Age 

The first atom was split in 1942 at exactly 3:25 p.m. on the University of Chicago grounds. The moment is regarded as the start of the atomic age. Henry Moore’s Nuclear Energy sculpture marks the spot today.

World’s Tallest Building Designed by a Female Architect 

It may not be the tallest building in Chicago (that honor goes to the Willis Tower, at 110 storeys) but the 82-storey Aqua is the tallest structure in the world to be designed by a woman, architect Jeanne Gang. According to the architect, its outstretched balconies reference the limestone outcrop features commonly found in the great lakes region — and serve the practical purpose of creating excellent views for residents!

First Televised Presidential Debate

You likely know that the first televised presidential debate is thought to have helped John F. Kennedy to win the 1960 election over Richard Nixon. The Chicago fact that may surprise you is that it was broadcast from Chicago’s CBS Studios!

World’s First Brownie

Good news: you can thank Chicago for the brownie. Bertha Palmer, wife of millionaire hotelier Potter Palmer, cooked up the fudgy squares for the first time at Chicago’s Palmer House, just in time for their debut at the 1893 World’s Columbian Exposition. And this is only one of Chicago’s famous foods

Find out More Chicago Facts & Fun at Willis Tower Skydeck!

When it comes to interesting facts about Chicago, the list really is endless. Not sure where to start? Get the big picture with a view from the Skydeck and gain a whole new appreciation of Chicago’s revolutionary grid layout. Contact us to learn more fun Chicago facts, or for more information about special events at the Skydeck and family-friendly activities on the 109th floor!