and most populated city and commune, with over 2.7 million
residents in 1,285.3 km2 (496.3 sq mi). In 2006 the population of the metropolitan area was estimated by the Organization for Economic Co-operation and Development to have a population of 3.7 million.
The city of Rome is located in the central-western portion of the Italian Peninsula, on the Tiber River within the Lazio region of Italy. Rome's history spans over two and a half thousand years. It was the capital city of the Roman Kingdom, the Roman Republic and the Roman Empire, which was the dominant power in Western Europe and the lands bordering the Mediterranean Sea for over seven hundred years from the 1st Century BC until the 7th Century AD. Since the 1st Century AD Rome has been the seat of the Papacy and, after the end of Byzantine domination, in the 8th century it became the capital of the Papal States, which lasted until 1870. In 1871 Rome became the capital of the Kingdom of Italy, and in 1946 that of the Italian Republic.
In 2007 Rome was the 11th-most-visited city in the world, 3rd most visited in the European Union, and the most popular tourist attraction in Italy. The city is one of Europe's and the world's most successful city brands, both in terms of reputation and assets. Its historic centre is listed by UNESCO as a World Heritage Site. Monuments and museums such as the Vatican Museums and the Colosseum are amongst the world's 50 most visited tourist destinations (the Vatican Museums receiving 4.2 million tourists and the Colosseum receiving 4 million tourists every year)