Grand Forks is the third-largest city in the U.S. state of North Dakota and the county seat of Grand Forks County. In July 2008, its population was estimated at 51,313, and it had an estimated metropolitan population of 97,279. Grand Forks, along with its twin city of East Grand Forks, Minnesota, forms the center of the Grand Forks, ND-MN Metropolitan Statistical Area, which is often called Greater Grand Forks or The Grand Cities. Located on the western banks of the Red River of the North in an extremely flat region known as the Red River Valley, the city is prone to flooding and was struck by the devastating Red River Flood of 1997. Originally called Les Grandes Fourches by French fur traders, Grand Forks was founded in 1870 by steamboat captain Alexander Griggs and incorporated on February 22, 1881. Its location at the fork of the Red River and the Red Lake River gives the city its name. Historically dependent on local agriculture, the city's economy now encompasses higher education, defense, health care, manufacturing, food processing, and scientific research. Grand Forks is served by Grand Forks International Airport and Grand Forks Air Force Base, while the city's University of North Dakota is the oldest institution of higher education in the state. The Alerus Center and Ralph Engelstad Arena host athletic and other events, while the North Dakota Museum of Art and Chester Fritz Auditorium are the city's largest cultural venues.