Columbus is the capital of and the largest city in the U.S. state of Ohio. The Columbus metropolitan area, which encompasses several counties, is the third largest in Ohio behind Cleveland and Cincinnati. Columbus is the fifteenth largest city in the United States of America. It is the county seat of Franklin County, yet the city has expanded and annexed portions of adjoining Delaware County and Fairfield County. Named for explorer Christopher Columbus, the city was founded in 1812 at the confluence of the Scioto and Olentangy rivers, and assumed the functions of state capital in 1816.
The population of the city was 787,033 at the 2010 census, making it the most populous city in Ohio. Although Columbus was the 15th largest city in the United States, its metropolitan area was 32nd largest, with 1,836,536 residents. It is the fourth most populous state capital in the United States. According to the U.S. Census Bureau, the Columbus Combined Statistical Area (which also includes Marion and Chillicothe) has a population of 2,031,229.
The city has a diverse economy based on education, government, insurance, banking, fashion, defense, aviation, food, clothes, logistics, steel, energy, medical research, health care, hospitality, retail, and technology. Columbus is home to the world's largest private research and development foundation, the Battelle Memorial Institute; Chemical Abstracts Service, the world's largest clearinghouse of chemical information; NetJets, the world's largest fractional ownership jet aircraft fleet; and The Ohio State University, the nation's largest campus.
In 2011, the city had five corporations in the U.S. Fortune 500, including Nationwide Mutual Insurance Company, American Electric Power, Limited Brands, Momentive Specialty Chemicals, and Big Lots. Major foreign corporations operating or with divisions in the city include Germany-based Siemens and Roxane Laboratories, Finland-based Vaisala, Tomasco Mulciber Inc., A Y Manufacturing, Yachiyo of America and US Yachiyo, Inc.