The last game at the Wells Fargo Center was March 11, and COVID-19 testing hasn’t been done at the stadium complex in South Philly in weeks. So why is the Wells Fargo parking lot full?

The question came to The Inquirer from a curious reader, who noticed the thousands of cars with license plates from across the United States parked onsite.

While the City of Philadelphia owns the underlying real estate of the parking lots at the stadium complex, the lots are leased to the companies that operate the venues including the Wells Fargo Center, Citizens Bank Park, and Lincoln Financial Field, according to Jessica Calter, spokesperson for the Philadelphia Industrial Development Corp. (PIDC), which manages properties and industrial sites on behalf of the city.

The city receives a parking tax for the lots, but parking operations, maintenance, and revenue are controlled by the teams, said mayoral spokesperson Kelly Cofrancisco.

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So why are the Wells Fargo lots so busy? The answer to the mystery: They’re all rental cars.

Given the “precipitous drop in air travel” over the last few months, rental car companies at Philadelphia International Airport found themselves with more cars on their hands than their airport lots could handle, Calter said.

“In an effort to address this, rental cars are being stored at off-site locations, including the Wells Fargo Center parking lots," she said.

Phil Weinberg, executive vice president and general counsel for Comcast Spectacor, which owns the Wells Fargo Center, said Enterprise is a corporate partner of the Flyers and the Wells Fargo Center, and it is the only company with rental vehicles parked at the stadium.

“They approached us shortly after the stay-at-home orders became effective and asked if we could assist them in parking their cars, which are clearly not in service right now,” he said.

Since Enterprise is a corporate sponsor, the Wells Fargo Center is not charging the company for parking approximately 2,200 of its vehicles on site, Weinberg said.

The parking agreement has no fixed end date, but the cars will be gone whenever the venue reopens to the public, he said.

The Wells Fargo Center isn’t the only sports venue in the country housing overflow rental vehicles. According to the Honolulu Star-Advertiser, Aloha Stadium has up to 1,500 rental cars from five companies parked in its lots.

And in Southern California, thousands of rental cars fill the parking lots at Dodger Stadium in Los Angeles and Angel Stadium in Anaheim, according to the Southern California News Group.