Holiday travel is expected to ramp up across the Philadelphia region starting Tuesday, according to travel experts, with more people taking to the skies and hitting the roads in the days leading up to the end of the year.

Jana Tidwell of AAA said about 90% of travelers in Philadelphia's five-county region are expected to drive to their destinations. She encouraged drivers to avoid peak travel times when possible.

"We will definitely feel traffic start to build late morning [Tuesday], through about 7 or 8 p.m.," Tidwell said. "So hit the road early in the morning, wait until late in the evening."

At Philadelphia International Airport, travelers were already moving through terminals Monday, a day before airport officials say the year-end holiday travel period officially begins. The airport projects air travel will be about 5% higher than the same period last year.

Between Tuesday and Jan. 4, more than one million passengers are expected to fly in and out of PHL, according to airport projections.

"I'm pretty excited to spend time with my loved ones," said Bentley Garcia, who was traveling to Colorado Monday evening.

Even ahead of the official rush, Garcia noted growing crowds inside the terminals. 

"It seems pretty busy here today," he said.

Airport officials say the heaviest travel days over the next two weeks are expected to be Friday, Dec. 26; Saturday, Dec. 27; and Monday, Dec. 29. Travelers are encouraged to allow extra time on those days.

Passengers are also reminded to check flight status with their airline before heading to the airport and to arrive at least two hours early for domestic flights and three hours early for international travel. TSA officials recommend using gift bags or boxes with removable lids when traveling with wrapped presents, in case additional screening is required.

Some drivers reported relatively smooth conditions Monday night, including a couple traveling from New York City to Delaware. 

"I expected it to be worse, honestly," said Caroline Thomas, who was traveling with Connor Hagan. 

"Yeah, we do it a lot," Hagan said.