![A monitor for United Airlines announces the cancellation of flights in and out of the San Francisco International Airport on September 11, 2001, due to the worst act of terrorism in U.S. A monitor for United Airlines announces the cancellation of flights in and out of the San Francisco International Airport on September 11, 2001, due to the worst act of terrorism in U.S.](https://c8.alamy.com/comp/2D3FH3B/a-monitor-for-united-airlines-announces-the-cancellation-of-flights-in-and-out-of-the-san-francisco-international-airport-on-september-11-2001-due-to-the-worst-act-of-terrorism-in-us-history-as-highjackers-took-over-four-airliners-crashing-two-of-them-into-the-world-trade-center-in-new-york-city-united-airlines-flight-93-traveling-from-newark-new-jersey-to-san-francisco-was-one-of-the-four-planes-hijacked-it-crashed-near-pittsburgh-pennsylvania-killing-all-45-people-aboard-2D3FH3B.jpg)
A monitor for United Airlines announces the cancellation of flights in and out of the San Francisco International Airport on September 11, 2001, due to the worst act of terrorism in U.S.
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United Airlines resumes SFO nonstops to popular U.S. and European destinations - San Francisco Business Times
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