The Odd Reason This Popular Airport In Illinois Is Missing A Whole Terminal

Chicago isn't only the home of deep-dish pizzas and the Cubs — it's the city where millions of travelers from all over the world stop, whether as an end destination or a mid-journey layover. According to OAG, Chicago's O'Hare Airport ranked as the ninth busiest airport in the world, with 43,708,796 scheduled plane seats linking to the hub in 2023.

Besides being busy, Chicago O'Hare is known as one of the best ports in the U.S., perhaps for its intriguing art installations and amenities for long layovers — think yoga classes and spa massages. But look a little closer, and you'll notice something peculiar about the popular airport: One of the terminals is missing.

When looking at the signs posted around O'Hare, it becomes clear that Terminals 1, 2, 3, and 5 exist, but Terminal 4 is nowhere to be found. The terminal was once on the airport maps, starting in 1985 when it was the latest addition to the hub's three terminals (the fifth would only come later). Back then, it was designated as an international terminal meant to help the airport keep up with growing traffic. However, by 1993, a bigger and better terminal was built, which soon overshadowed the humble fourth wing.

When the new international terminal opened at O'Hare in the early 1990s, the airport's planners didn't know exactly what to do with Terminal 4. As David Woodcock, O'Hare's international terminal airline representative, shared with WGN9, the fourth terminal was a temporary solution while the airport continued building a larger space. When the construction was completed in 1993, O'Hare initially used the original Terminal 4 for departures and the newly built terminal for arrivals. "But then the dilemma came that there would be two Terminal 4s," Woodcock explained. "That would be very confusing to everybody. So we talked to the city [...] and we agreed Terminal 5 should be the name of the new terminal."

Eventually, the old terminal became redundant and was scrapped altogether, which explains why you'll no longer find a Terminal 4. However, if you're feeling nostalgic, you can visit the site at O'Hare's bus shuttle depot on the ground level of the parking garage — just be warned that it looks much different today than it did in 1985.

Note that Terminal 4 also has a small chance of making a comeback in the future. In 2009, Gregg Cunningham, a spokesman for the Chicago Department of Aviation, revealed to TimeOut that Terminal 4 would be resurrected in a new building. Over a decade later, it's unclear if the projection still holds up, although the airport has expanded Terminal 5 and is reportedly developing a global terminal to replace Terminal 2.