Piraeus of social problems also emerged with the concentration of new populations in the suburbs of the old city, such as Nikaia, Keratsini, Drapetsona and Korydallos. The involvement of Greece in World War II came as a major setback to the city's progress. After the war, the city began its development once more, as damage to the port and the city were repaired and new additions took shape after 1955. Piraeus is now the third largest municipality in Greece; the city proper with its suburbs form the Piraeus urban area, which is incorporated in the Athens urban area, thus making Piraeus
Port of Piraeus for top 100 container ports in 2015 Piraeus ranked 8th in Europe and 3rd the Mediterranean sea. The port of Piraeus is expected to become the busiest port of the Mediterranean in terms of container traffic by 2019. Until the 3rd millennium BC, Piraeus was a rocky island connected to the mainland by a low-lying stretch of land that was flooded with sea water most of the year. It was then that the area was increasingly silted and flooding ceased, thus permanently connecting Piraeus to Attica and forming its ports, the main port of Cantharus and the two smaller of