Miami County Ohio (Historic Districts) has 6 places on the National Register of Historic Places including 4 places of Statewide significance. Significant places include Hobart Circle Historic District, Lockington Locks Historical Area, Piqua-Caldwell Historic District and Troy Public Square and Elizabeth Township Rural Historic District.
Some of the country's most noteable architects helped create the Miami County places including Hobart Welded Steel House Co.. Prominent architectural styles found in Miami Country are Federal, Late Victorian and Colonial Revival.