San Francisco International Airport is being described as "a travelers' nightmare", after an ongoing construction project at one of their runways forced the delay and cancelation of hundreds of flights Sunday and Monday.

The culprit is Runway 28L, which NBC Bay Area reports is typically used for arriving flights. As part of a planned upgrade to the runway, which includes repaving and the addition of a line of LED lights down its middle, SFO says the runway will be closed for business from 6 p.m. Fridays to noon Mondays for nine weekends from March 31-June 16.

The runway will remain open on Memorial Day weekend, officials say.

When the closures were announced, SFO officials said that “This project will require runway and taxiway closures which will affect normal operations. Some delays may occur during weekend closures.” They sure weren't kidding, as Sunday saw more than 370 delays and 155 cancellations, KRON 4 reports. According to ABC 7, "some incoming flights had to be diverted to San Jose or Oakland. Passengers were then bussed to SFO."

Passengers NBC spoke with complained about being delayed at the airport overnight as a result of the construction, with one saying that she'd been trying to get home to home to Eugene, Oregon, since Saturday night.

"We landed last night at 11 p.m.," she said. "Waited here until 7 a.m., out by 11."

Another passenger complained of similar issues, saying that first her flight "was delayed four hours...Then we couldn't get a flight until 24 hours later." (Someone get these passengers a therapy pig, stat!)

The problems continue today, according to KRON 4. As of 4:30 a.m. Monday, 51 flights were cancelled and 30 more flights (ten arrivals and 20 departures) experienced significant delays. Expect that number to keep climbing, as officials say it's likely delays and cancellations "will increase throughout the day."

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