() is a city in the U.S. state of Ohio and the county seat of Allen County. The municipality is located in northwestern Ohio along Interstate 75 approximately 72 miles (116 km) north of Dayton and 78 miles (125 km) south-southwest of Toledo.
As of the 2000 U.S. census, the city had a population of 40,081. It is the principal city of and is included in the Lima, Ohio Metropolitan Statistical Area, which is included in the Lima-Van Wert-Wapakoneta, Ohio Combined Statistical Area. Lima was founded in 1831.
According to the United States Census Bureau, the city has a total area of 12.9 square miles (33.4 km²), of which, 12.8 square miles (33.1 km²) of it is land and 0.1 square miles (0.3 km²) of it (0.78%) is water.
The Ottawa River flows through the city. Locals sometimes refer to the river as "Hawg Creek". This resembles a traditional local name used dating back to the Hog Creek Shawnee community that existed between Lima and present Ada, prior to the Shawnee removal of 1831. This removal made possible the official founding of "Lima" as a formal town in that year.
Lima is at the intersection of State Route 309 (the original Lincoln Highway) and Interstate 75, which replaced U.S. Route 25, one of the routes of the Dixie Highway.