Campania is an administrative region of Italy located in Southern Italy; most of it is in the south-western portion of the Italian Peninsula, but it also includes the small Phlegraean Islands and the island of Capri. The capital of the Campania region is Naples. As of 2018, the region had a population of around 5,820,000 people, making it Italy's third most populous regiā¦Campania is an administrative region of Italy located in Southern Italy; most of it is in the south-western portion of the Italian Peninsula, but it also includes the small Phlegraean Islands and the island of Capri. The capital of the Campania region is Naples. As of 2018, the region had a population of around 5,820,000 people, making it Italy's third most populous region, and, with an area of 13,590 km², its most densely populated region. Based on its GDP, Campania is also the most economically productive region in Southern Italy and the 7th most productive in the whole country. Naples' urban area, which is in Campania, is the eighth most populous in the European Union. The region is home to 10 of the 58 UNESCO sites in Italy, including Pompeii and Herculaneum, the Royal Palace of Caserta, the Amalfi Coast, the Longobardian Church of Santa Sofia in Benevento and the Historic Centre of Naples. In addition, Campania's Mount Vesuvius is part of the UNESCO World Network of Biosphere Reserves. The Region plays also a key international role in international diplomacy, since it is home to NATO's Allied Joint Force Command Naples and of the Parliamentary Assembly of the Mediterranean.