Travelers returning home after Christmas and other passengers are keeping Hartsfield-Jackson busy.
Security lines stretched from checkpoints at the Atlanta airport on Wednesday morning, with wait times reaching 15 to 30 minutes.
Hartsfield-Jackson, the world's busiest airport, expects to handle more than 4.2 million passengers over the holiday period running from Dec. 16 through Jan. 3.
Wednesday is not one of the busiest days of the holiday period, with Friday Dec. 30, Monday Jan. 2 and Thursday Jan. 5 expected to bring bigger crowds.
The airport is urging travelers to arrive at Hartsfield-Jackson at least two hours before domestic flights and 2.5 hours before international flights.