Lisbon is the capital and the largest city of Portugal, with a population of 552,700 within its administrative limits in an area of 100.05 km².Its urban area extends beyond the city's administrative limits with a population of around 2.7 million people, being the 11th-most populous urban area in the European Union. About 2.8 million people live in the Lisbon Metropolitan Area (which represents approximately 27% of the country's population). It is continental Europe's westernmost capital city and the only one along the Atlantic coast. Lisbon lies in the western Iberian Peninsula on the Atlantic Ocean and the River Tagus. The westernmost areas of its metro area are the westernmost point of Continental Europe. Lisbon is recognized as a global city because of its importance in finance, commerce, media, entertainment, arts, international trade, education and tourism. It is one of the major economic centers on the continent, with a growing financial sector and one of the largest container ports on Europe's Atlantic coast. Lisbon Portela Airport serves over 20 million passengers annually, as of 2015, and the motorway network and the high-speed rail system of Alfa Pendular connect the main cities of Portugal. The city is the 7th-most-visited city in Southern Europe, after Istanbul, Rome, Barcelona, Madrid, Athens and Milan, with 1,740,000 tourists in 2009. Lisbon is one of the oldest cities in the world, and the oldest in Western Europe, predating other modern European capitals such as London, Paris and Rome by centuries. Julius Caesar made it a municipium called Felicitas Julia, adding to the name Olissipo. Ruled by a series of Germanic tribes from the 5th century, it was captured by the Moors in the 8th century. In 1147, the Crusaders under Afonso Henrique’s reconquered the city and since then it has been a major political, economic and cultural center of Portugal. Unlike most capital cities. Lisbon enjoys a Mediterranean climate. It has the warmest winters of any metropolis in Europe, with average temperatures 15 °C (59 °F) during the day and 8 °C (46 °F) at night from December to February. The typical summer season lasts about six months, from May to October, although also in April temperatures sometimes reach around 25 °C (77.0 °F).