TORONTO – A record 27 million people have booked flights for travel in the U.S. between Nov. 18-29, making this Thanksgiving holiday one of the busiest in history.

While time with family and friends, not to mention a perfectly roasted turkey, are definite upsides to the busy season, for many travellers the nightmare of getting to their destination far outweighs the perks. Flight delays are pretty much guaranteed with this massive influx in traffic, but new data by travel research site WanderBat may give travellers the chance to redirect their plans to avoid any unnecessary headaches.

After sifting through six years of Thanksgiving flight data between 2010-2015 from the Bureau of Transportation Statistics, reports Vox, WanderBat was able to compile a list of all flights with a delay of 15 minutes or more. They limited their analysis to the day before Thanksgiving and Thanksgiving Day, and made the cutoff airports with a minimum of 200 combined flights over the six-year period.

The results show that Chicago in particular fared poorly, not to mention New York, claiming five spots on the top 25 most-delayed airports list.