what is their main source of economy?
Important Greek companies have their headquarters in the metropolitan area of Athens and multinational companies also have their regional research and development headquarters there
Athens
Important Greek companies such as Hellenic Aerospace Industry, Hellas Sat, Mytilineos Holdings, Titan Cement, Hellenic Petroleum, Papadopoulos E.J., Folli Follie, Jumbo S.A., OPAP, and COSMOTE have their headquarters in the metropolitan area of Athens. Multinational companies such as Ericsson, Sony, Siemens, Motorola, Samsung, Microsoft, Novartis, Mondelez, Coca-Cola, etc. have their regional research and development headquarters also there. 
what is alcibiades? A prominent Athenian statesman, orator and general who were his parents? Cleinias and Deinomache when was he appointed as the general? UNANSWERABLE can you tell me something about his birthplace? The city of Athens during the classical period of ancient Greece was the major urban center of the notable polis of the same name, located in Attica, Greece where did the city get its name from? The root of the word is probably not of Greek or Indo-European origin and is possibly a remnant of the Pre-Greek substrate of Attica what kind of weather do they have? Hot-summer Mediterranean climate can you tell me more about their architecture? It incorporates architectural styles ranging from Greco-Roman and Neoclassical to modern times what is their estimated population? 664,046
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Athens [SEP] Economy and infrastructure
Athens is the financial capital of Greece. According to data from 2014, Athens as a metropolitan economic area produced 130 billion US-dollars as GDP in PPP, which consists nearly a half of the production for the whole country. In the list with the strongest economic metropoles of the world Athens was ranked that year 102nd, while the GDP per capita for the same year was 32,000 US-dollars. Athens is one of the major economic centres in south-eastern Europe and is considered as a regional economic power in Europe generally. The port of Piraeus, where big investments by COSCO have already been delivered during the recent decade, the completion of the new Cargo Centre in Thriasion, the expansion of the Athens Metro and the Athens Tram, as well as the projected metropolitan park in Elliniko and other economic projects are the economic landmarks of the upcoming years.