It used to be you’d circle the airport loop, get chased away from baggage claim by police or park precariously on the shoulder of ramps and roadways.

That was before Philadelphia International Airport opened a convenient 150-space cellphone waiting lot in December 2009 on airport property — just one minute from the terminals.

Great. Terrific. Handy. Easy to find. And, best of all, free.

Since tighter post-Sept. 11, security, cellphone lots — free parking areas where people picking up travelers can wait — have sprung up at many of the largest U.S. airports.

“The word has gotten out, and it’s been very well-received,” said Keith Brune, deputy director of Philadelphia airport operations.

Drivers interviewed recently among about 80 to 100 cars streaming into the lot were enthusiastic.

“It’s wonderful to have this and not have to go into short-term parking, and worry that if the flight is delayed, you will have to pay extra,” said Jamie Kravec of West Chester, Pa., waiting for the “I’m here” call from her boyfriend, flying in from Seattle.

“There’s less hassle. We used to sit out on the highway waiting for people,” said Joyce Miller of Townsend, Del., who with her husband, Arthur, was picking up a family member from Tennessee.

“It’s beautiful that they’ve got all these flight display boards,” she said. “It’s a sign of the times. We all use cellphones.”

Improving traffic safety and congestion was a key motive for the lots. Since 9/11, the Transportation Security Administration has not allowed cars to linger at baggage claim.

Cellphone lots range from a paved lot to a complex with portable toilets, electronic flight display screens, food and free Wi-Fi.

The Charlotte, N.C., airport has two cellphone lots; Phoenix Sky Harbor Airport has three.

Pittsburgh International offers the first hour of parking for free in the “extended-term” parking lot; the second hour costs $1.

The airport in Portland, Ore., is seeking a developer to build a fuel, convenience store and fast-food “travel center” where those waiting for flights can grab coffee and fill up their gas tank while keeping tabs on a flight’s status.

Cincinnati’s airport plans to put a gas station at its entrance road with a larger waiting area, convenience store and a Subway or Dunkin’ Donuts, said Paul Hegedus, the airport’s vice president of commercial management.

Denver International Airport will relocate its cellphone lot next to a gas station and a Wendy’s. “When the new waiting area opens this fall, it will have a food court with a Subway, Dunkin’ Donuts, Baja Fresh Mexican Grill, and Zpizza,” said airport spokeswoman Julie Smith.

The Tampa, Fla., airport’s cellphone lot features food trucks, Wi-Fi and a pavilion with restrooms and vending machines.

“Some people will come just for the food truck, not even to pick up a passenger,” said airport spokeswoman Janet Zink. A list of food trucks is posted weekly on the airport’s Facebook page.

Many cellphone lots are basic parking areas, lighted at night and patrolled by police but without concessions or restrooms. They include Baltimore-Washington International, Los Angeles, Washington Dulles, and Reagan National airports.

Between 4 and 10 p.m., when Philadelphia airport is busiest, the cellphone lot consistently has 75 or 80 cars — and is 100 percent full around holidays.

The lot was packed before 5 p.m. on a recent weekday and another dozen cars were parked on Route 291, just outside the cellphone lot. In one of them, Derrick Gray of Lumberton, N.J., said he drove through the lot once and, not finding a space, looped around and parked on 291.

“It’s an overflow crowd here. I think it could have been a little bigger,” he said, referring to the lot. “It beats riding around the airport.”

With a dozen signs directing motorists to the spot, Pennsylvania state police are issuing fewer tickets to drivers parked illegally on ramps.

But some cars still congregate haphazardly on roadways.

“I am told that we are still having an issue with people parking on the side of roads,” said State Police Capt. James P. Raykovitz. “Our guys consistently are moving people along and occasionally writing tickets.”

Philadelphia airport has no plans to add bathrooms or refreshments. “Our position is it’s a short-term, safe, off-the-road, convenient waiting lot,” Brune said. “First off, we are very land-constrained.”

Minutes from the cellphone lot is a Wawa convenience store with gas and food. Drivers can also park in an airport garage and go into a terminal, or head to nearby Tinicum Township, Pa., “and there are amenities there,” Brune said.

Did motorists waiting recently for passengers have suggestions?

“Potentially put in a rest area — bathrooms of some sort,” said Leigh Walker of Manahawkin, N.J., waiting to pick up his girlfriend. “A lot of people would really appreciate it.”

Dan Rapak of Reading, Pa., would like to see the “no idling” signs come down because “in 90- or 100-degree weather, you are going to sit here with no air-conditioning.” The signs ask parked motorists to turn off car engines.

Joshua Kocses of Princeton, N.J., said that if there were more space, he’d like to see a concession stand. “Other than that, it’s definitely convenient. It’s nice to drive and not pay for parking. Plus, I can just sit here and eat or work, do whatever I’ve got to do.”