Piraeus is the third largest settlement of Greece and is the heart of the Municipality of Piraeus. Piraeus is the city of Athens and the biggest port of Greece and the eastern Mediterranean. Piraeus is the busiest port in Greece, the largest port in Europe and the third in the world with respect to the carriage of passengers, serving nearly 20 million passengers a year to go to the Aegean islands and abroad.
Divided into three smaller ports: the central port, the Zea Marina and Mikrolimano. Piraeus in modern times is the largest industrial center of the country. The center of Piraeus is about 10 km from the center of Athens. As part of urban Athens complex serves transportation by various means: buses, trolley buses, the suburban railway, tram Athens and the Athens Metro, presently the old line of electric railway and the future of the extension of the subway line, while connected and to the railway network OSE.