Rome (Italian: Roma) is the capital city of Italy and of the Lazio region, as well as the country's largest and most populous comune, with about 2.8 million residents (3.8 million considering the whole urbanised area, as represented by the Province of Rome). It is located in the central-western portion of the Italian peninsula, where the river Aniene joins the Tiber. As one of the largest cities in the European Union, the Comune di Roma has a gross domestic product of €97 billion in the year 2005, equal to 6.7% of Italy's GDP — the highest proportion of GDP produced by any single Italian comune. The current Mayor of Rome is Walter Veltroni.