In 2015, Atlanta’s airport became the first to top 100 million passengers in a calendar year, serving more than 101 million travelers. Beijing’s airport was a distant second in the world, with nearly 90 million passengers last year. The next busiest U.S. airports were those serving Chicago (No. 4 in the world, 76.9 million), Los Angeles (7th, 74.9 million), and Dallas-Ft. Worth (10th, 63 million).