Turin is a major city as well as a business and cultural centre in northern Italy, capital of the Piedmont region, located mainly on the left bank of the Po River surrounded by the Alpine arch. The population of the city proper is 909,193 (November 2008) while the population of the urban area is estimated by Eurostat to be 1.7 million inhabitants; the Turin metropolitan area is estimated by OECD to have a population of 2.2 million. Turin is a flourishing, industrious and cosmopolitan European city, which enjoys state-of-the-art technology and architectural developments. The city boasts a rich culture and history, and is known for its numerous art galleries, restaurants, churches, palaces, operahouses, piazzas, parks, gardens, theatres, libraries, museums and other venues. Turin is well-known for its baroque, rococo and neo-classical architecture. Much of the city's public squares, castles, gardens and elegant palazzi (such as Palazzo Madama), were built by Sicilian architect Filippo Juvarra, who modeled these buildings on the Baroque and classical style of Versailles. Examples of these French-themed edifices include the Royal Palace of Turin, the Palazzina di caccia of Stupinigi and the Basilica di Superga. Turin is sometimes called the "cradle of Italian liberty", due to its having been the birthplace and home of notable politicians and people who contributed to the Risorgimento, such as Cavour. The city currently hosts some of Italy's best universities, colleges, academies, lycea and gymnasia, such as the Polytechnic University of Turin. Prestigious and important museums, such as the Museo Egizio and the Mole Antonelliana are also found in the city. Turin's several monuments and sights make it one of the world's top 250 tourist destinations, and the tenth most visited city in Italy in 2008. Turin used to be a major European political centre, being Italy's first capital city in 1861 and being home to the House of Savoy, Italy's royal family. Even though much of its political significance and importance had been lost by World War II, it became a major European crossroad for industry, commerce and trade, and currently is one of Italy's main industrial centres, being part of the famous "industrial triangle", along with Milan and Genoa. Turin is ranked third, after Rome and Milan, for economic strength. With a GDP of $58 billion, Turin is the world's 78th richest city by purchasing power, and even though the city was unable to become a "world city", unlike Milan or Rome, it was ranked by GaWC as "economically efficient", along with Jerusalem, Genoa, Macau, Marseille, Liverpool, Strasbourg, Salt Lake City, Seville and Tijuana, to name a few.Turin is also home to much of the Italian automotive industry. Turin is well known as the home of the Shroud of Turin, the football teams Juventus F.C. and Torino F.C., the headquarters of automobile manufacturers Fiat, Lancia and Alfa Romeo, and as host of the 2006 Winter Olympics. Several International Space Station modules, such as Harmony and Columbus, were also manufactured in Turin. It was the capital of the Duchy of Savoy from 1563, then of the Kingdom of Sardinia ruled by the Royal House of Savoy and finally the first capital of a unified Italy. It is often referred to as "the Capital of the Alps". Turin is also known as "the Automobile Capital of Italy" or the Detroit of Italy; in Italy it is also called "[La] capitale Sabauda".