Bellefontaine (bĕlfounˈtĭn, –fŏnˈtĭn) [key], city (1990 pop. 12,142), seat of Logan co., W central Ohio; settled 1818, inc. 1835. It is a trade and rail center for a farm area. Manufactures include electrical equipment, small motors, and tools. East of the city is Campbell Hill, the highest point in Ohio (1,550 ft/472 km).