Large crowds at airports and traffic on roads were expected Sunday, which marks one of the busiest travel days of the year.

A record 28.5 million people were expected to fly on U.S. airlines between Friday and Tuesday, Nov. 28.

Sunday is expected to be the busiest of day of all, with an estimated 2.88 million people taking to the skies.

Triple-A says nearly 51 million Americans traveled 50 miles or more for Thanksgiving, an increase of more than 3 percent from last year.

It says 44 million of those travelers are driving. 

The national average gas price is $2.56 per gallon.