Naples is the regional capital of Campania, Italy. With a population of 908,082 within the city's administrative limits, it is the largest city in southern Italy and the third-largest city of Italy after Rome and Milan, while its province-level municipality is the third most populous metropolitan city in Italy with a population of 2,958,410 residents. Its metropolitan area, the seventh most populous in the European Union, stretches beyond the boundaries of the city wall for approximately 30 kilometres. Naples also plays a key role in international diplomacy, being home to NATO's Allied Joint Force Command Naples and the Parliamentary Assembly of the Mediterranean.