Reggio Emilia is a city in northern Italy, in the Emilia-Romagna region. It has about 171,944 inhabitants and is the main comune of the Province of Reggio Emilia.
The town is also referred to by its more official name of Reggio nell'Emilia. The inhabitants of Reggio nell'Emilia usually call their town by the simple name of Reggio. In some ancient maps the town is also named Reggio di Lombardia.
The old town has a hexagonal form, which derives from the ancient walls, and the main buildings are from the 16th–17th centuries. The comune's territory is totally on a plain, crossed by the Crostolo stream.