BERKELEY, California (AP) — The Fourth of July holiday weekend is jamming US airports with their biggest crowds since the pandemic began in 2020.

About 2.49 million passengers went through security checkpoints at US airports Friday, surpassing the previous pandemic-era record of 2.46 million reached earlier in the week, according to figures released Saturday by the Transportation Security Administration (TSA).

The escalating numbers show leisure travellers aren’t being deterred from flying by rising fares, the ongoing spread of COVID-19 or worries about recurring flight delays and cancellations.

Friday’s passenger volume marked a 13 per cent increase from July 1 last year, which fell on the Thursday before Fourth of July. This year’s number of passengers going through US airports also eclipsed the 2.35 million screened at security checkpoints on the Friday before the Fourth of July in 2019, but that was nearly a week ahead of Independence Day.

In a more telling sign of how close US air travel is reverting to pre-pandemic conditions, an average of 2.33 million passengers have passed through security checkpoints at domestic airports during the seven days ending July 1. That was close to the seven-day average of roughly 2.38 million passengers during the same 2019 period, according to the TSA.

But airlines have struggled to keep up with the surging demand amid staffing shortages and an assortment of other issues that have resulted in recurring waves of exasperating flight delays and cancellations that have been transforming some vacations into nightmarish ordeals.

Many airlines, including Delta, Southwest and JetBlue, have responded to the challenge by curtailing their summer schedules in an effort to reduce the inconveniences — and backlash — caused by flight delays and cancellations They are using larger planes on average to carry more passengers while they scramble to hire and train more pilots.

The headaches continued Friday, although they weren’t as bad as they have been at other times in recent months. There were more than 6,800 flight delays and another 587 flight cancellations affecting US airports Friday, according to the tracking site FlightAware. More than 2,200 delays and more than 540 flight cancellations had been recorded as of late Saturday morning.

Besides the flight delays and cancellations, travellers also have had to pay higher prices for tickets driven up by soaring fuel costs and other inflationary factors, as well as navigate around the health risks posed by continuing COVID-19 infections.

The travel bug is also congesting highways, even with the national average price for gasoline hovering around $5 per gallon — and above $6 per gallon in California and all its popular tourist attractions. AAA predicts that nearly 48 million people will travel at least 50 miles or more from home over the weekend, slightly fewer than in 2019.