United Airlines
United Airlines, Inc. is a major airline in the United States headquartered at the Willis Tower in Chicago, Illinois. United operates an extensive domestic and international route network across the United States and all six inhabited continents primarily out of its eight hubs, with Chicago–O'Hare having the largest number of daily flights and Denver carrying the most passengers in 2023. Regional service is operated by independent carriers under the brand name United Express. United was formed by the amalgamation of several airlines in the late 1920s, the oldest of these being Varney Air Lines, created in 1926 by Walter Varney who later co-founded the predecessor to Continental Airlines. In 1997, United became one of the five founding airlines of Star Alliance, of which it remains a member today. Since its merger with Continental in 2010, United consistently ranks as one of the world's largest airlines; it is currently first by the number of destinations served and second in terms of revenue and fleet size.
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