Four out of every 10 Washingtonians will travel 50 miles or more for Christmas this year --with regional travel up 2 percent from last year, AAA Mid-Atlantic reports.

Ninety percent of the 2.3 million travelers from the Washington region will travel by car, though 6 percent will fly, and another 4 percent will use other forms of travel, AAA found.

"During Christmas and New Year's we will experience the highest travel volume this decade, especially by the roadways, the railways, and the waterways," AAA Mid-Atlantic's John Townsend said in a statement. "The one exception is the airways, and this year, even that is making a comeback."

At $3.25 per gallon nationwide now, AAA expects gas prices to continue giving travelers holiday cheer after falling 7 percent last month -- the biggest monthly drop in four years.

AAA Mid-Atlantic warned that highways, airports and Union Station will be crowded over the holiday travel period, from Dec. 22 to Jan. 1.