A power outage at Hartsfield-Jackson Atlanta International, the world’ busiest airport, left thousands of travelers stranded in the dark for hours. The blackout shut down all airlines and aircraft, and hit the facility around 1 p.m. on Sunday. The power was not fully restored at the airport until around 11:45 at night. Reports have indicated that the power failure may have been caused by a faulty switch in a nearby underground electrical facility that caught on fire. The flames caused extensive damaged to the facility, and had to be put out before Georgia Power could enter the facility and restore power.

The City of Atlanta opened up the Georgia International Convention Center as a temporary shelter, and provided shuttle service to anyone that needed a place to stay for the night. Reports indicate that around 5,000 meals were also provided to passengers affected by the shutdown. The airport also stated that it will waive parking fees at the airport until 8 a.m. on Tuesday for affected travelers. The fiasco resulted in the cancellation of more than 1,000 flights during one of the busiest travel weeks of the year.

Delta Air Lines, in which Atlanta is its main hub of operations, canceled approximately 900 flights Sunday as a result of the power failure. Another 48 flights also had to be diverted to alternate airports due to the shutdown in Atlanta. The airline originally stated that operations would begin in full on Monday morning, but then issued a follow up statement that it expects up to 300 early-morning flights to be cancelled. Customers are being encouraged to check their flight status Monday morning before heading to the airport. Delta also stated that it will offer travelers affected by the shutdown a “one-time” change to tickets without fee for flights through Tuesday.