Fostoria (/fɒsˈtʊəriːə/, foss-TORR-EE-ə) is a city located at the convergence of Hancock, Seneca, and Wood counties in the northwestern part of the U.S. state of Ohio. The population was 13,046 at the 2020 Census, slightly down from 13,441 at the 2010 Census. It is approximately 40 miles (64 km) south of Toledo and 90 miles (140 km) north of Columbus. The community grew substantially during the end of the 19th century, coinciding with the northwest Ohio gas boom. Typical of Rust Belt cities, Fostoria peaked in size in 1970.