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
Piraeus also supplemented and modernised, with dredging operations, the construction of the Royal Landing, the Troumba Pier and the quay-ways up to the Customs House area, the commencement of construction work on the Outer Moles and the completion of permanent dry-docks. At the end of the 19th century, Piraeus had a population of 51,020 people. The establishment of the Port Committee in 1911, which controlled the works of construction and maintenance of the port, and the Piraeus Port Authority in 1930, which made a more efficient job of managing a port slowly increasing in traffic, played a catalytic role in the